Category Archives: cities


Rotterdam is one of the world’s great ports. It is also a center of modern architecture, owing in large part to bombing during World War II by the Nazis. Today, Rotterdam – The Hague area (including Delft) has 2.9 M people, and so is comparable in size with Minneapolis – St. Paul. Rotterdam is about 25 km from The Hague (but only 15 km from Delft (about the distance from Minneapolis to St. Paul)). Yet unlike the Twin Cities, there are farms between the cities, the Netherlands has done much to preserve its Green Heart. This undoubtedly drives up land prices in the developed areas, and makes it more difficult to have US-like suburbanization. In general the cities of the Netherlands are not as dense as the densest parts of US cities such as Minneapolis, but the “urbanized areas” are much denser than the least dense parts of those same metropolitan areas.

Some 239 photos, mostly of Rotterdam (some of the Delft train station on the way to Rotterdam), can be seen on Flickr. Selections are below.

I spent the morning just walking around, and the afternoon, walking around with David King.

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1. As in Delft, and Vienna, and just about everywhere else in Europe, there is a new train station. Rotterdam Centraal Station just opened, and the interior of the station is nice, and the exterior clearly exudes futurism. The plaza in front of the station is too large for my taste, and seems unprogrammed. There is a very large parking garage (ramp) under this plaza. The parking entrance echoes the train station.

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2. The public transit is excellent, there are modern trams on the major streets. There is also a modern subway, and a new LRT connecting to Delft (as well as the intercity train), thereby providing both local and express services.

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3. There are many pedestrianized streets. This is true both in the older areas as well as some newer developments. Absence of cars has not obviously hindered retail sales.

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4. It seems as instead of hauling wet cement trucks through the city, the require construction to make it onsite, and thus only have to haul aggregate, and letting the construction firm mix local water. This reduces wear on the streets from some of the heaviest vehicles around.

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5. Car sharing is becoming more visible, e.g. Green Wheels are widely available.

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6. Electric vehicles, and charging stations are also becoming visible.

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7. Cycling is popular (relative to the US), though not as popular as Delft (see upcoming posts). Bike parking and Cycletracks are common features in the environment (also, hopefully unrelated, the ad seems to indicate that prostitution is legal.)

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8. They try to make use of the area under bridges and viaducts, in this case for a trampoline. Notably the trampoline was being used and had not been obviously vandalized.

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9. Attempts at creating a roundabout on a local shopping street using simply paint and brick patterns did not seem to succeed.

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10. The sidewalks are often continuous elevation across streets (i.e. there is no cross-walk, there is a cross-drive). This helps remind drivers they are entering a woonerf. Drivers must slow down since they are crossing the pedestrian right-of-way, rather than vice-versa. If there is one thing I could do to American residential neighborhoods, it would be implementing the woonerf. If there is one thing I would build to tell drivers they are in woonerfs, it would be this sidewalk extension across the local street (when it joins a major road) as a way of signaling to drivers they are in a new space> This is far more effective than signs or changes in pavement surfaces alone. (To be clear, “complete streets”, while better than incomplete streets, are not woonerven, despite what wikipedia says.)

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11. There are lots of wayfinding aids, moreso in the Museum Quarter. (Sadly museums are closed on Mondays).

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12. Even though museums are closed, public art is pervasive.

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13. The Dutch are excellent at waste removal. Putting trash in the receptacles in the first place is a bit more difficult. Note the receptacles are atop larger subterranean canisters, and will be sucked out with giant vacuum like devices.

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14. Ducks establish small well-defended Duckdoms on little islands in the canals (atop some type of pipe).

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I recently spent a week in Delft for the WSTLUR conference. My visits to Rotterdam and Houten are detailed in other posts.

As a place to consider the relationship between transport and land use (the mission of both WSTLUR and, Delft provides an ideal place that should be used as a model for emulation by planners.

Like most travelers I arrived in Delft via train (from Schiphol Airport). Aside from payment issues that Americans face due to lack of PIN and Chip (which will be rectified in 2015), train is extremely convenient, running on a frequent intercity schedule, even at 6:30 am on a Sunday morning, even with works being undertaken. It is a little bit confusing for the non-Dutch speaker, especially when certain trains don’t follow the printed schedule, but the electronic message boards will state which trains go to which destinations. However while the platform is usually given, the track may be dynamic, so pay attention. In any case, you can just ask a native (they are taller than you), almost all of whom speak English.

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On the train it is even simpler.

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Delft has an old railroad station that has seen better days. It is near the Tram Line, but due to works, the exit path is a bit circuitous.

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The new train station will be open soon, I am not clear if they are adding tracks.

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Lots of bikes park at the station.

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Along just about any street of importances, where bikes are cars don’t share space, bikes have dedicated, separated cycle tracks, lanes parallel to, but separated from, the adjacent motor vehicle lanes. These cycletracks, and the bike trails in general, are also apparently open to mopeds and motor scooters. Sometimes it is separated by short concrete barriers that allow water to flow. These appear to be retrofits.

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The separation is often done by vertical rather than horizontal spacing, that is, the cycle track is immediately adjacent to the roadway, but elevated maybe 10 cm.

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Cars are allowed for residents, but retractable bollards keep non-residents and unauthorized vehicles from driving and parking on local streets. (Some tour buses seem permitted as well).

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The canals define the city.

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There are pedestrian/bike/motorbike tunnels that are widely used despite US fears of unsafety and graffiti.

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The tunnels themselves may be below sea level

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The town square (the Markt in Centrum) is programmed with lots of activities on the weekend. On Sunday it was innovative environmental technologies …

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and acrobats.

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Another square (De Beestenmarkt, where various beasts were once traded) is home to outdoor drinking and dining.

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Saturday is market day.

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The public transport buses in town are contracted out to a private company Veolia.

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In many places, there are shared spaces, including both commercial districts,

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along the canals,

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and residential neighborhoods.

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Delft is a tourist destination in its own right, and adjacent to a major university: TU Delft, thereby generating additional demand.
The campus of TU Delft is getting a tram, but in the meantime relies on bus.

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In short, it is beautiful. The buildings are (mostly) beautiful. The canals are beautiful. The public squares are beautiful. The cobblestone streets are beautiful. The massing and scale is beautiful. Also, it is entirely walkable or bikeable.

My Flickr sets are here 1, 2, 3, 4, and 5.

Vienna waits for you

Cross-posted at

I was recently invited to visit Austria by Advantage Austria as part of a delegation to learn about their Smart Grids and Smart Networks. But what I really wanted to see was the legendary city of Vienna, at whose gates the Ottomans were halted. Those defensive walls are no longer present, and it is their destruction and replacement which has shaped the Viennese transport network and development pattern.


Central Vienna
Central Vienna

Compare maps of Vienna and Minneapolis and you see some surprising similarities in shape at the same scale. To the north and east is the River (the Donau Canal (an offshoot of the main river) in Vienna, the Mississippi in Minneapolis). The Mississippi is mightier. In contrast to my anticipations, the Danube is far from romantic, and separated from the city by rail and highway. It is no Seine, or even a Thames, or even a Mississippi. It was straightened and re-organized as a flood control project.

Central Minneapolis
Central Minneapolis

The Innere Stadt was the early walled city (District 1). After a second ring of territories (Districts 2-8) were annexed in 1850, the walls were razed in 1857. The land housing the former defensive walls and plains became the Ringstrasse, and was lined with important public buildings. Think of District 1 as the CBD. There is far more commercial density in the Minneapolis CBD (defined by the area with tall buildings > 10 stories) than in the similar area of Vienna, which retains its Austro-Hungarian Empire height limits of about 7 stories. But there are far more stores, and people out and about in Vienna. There are several pedestrianized streets, lined with shops and active travelers. This is in part because of the mix of tourist attractions, cultural venues, residences and offices attracting visitors, residents, and workers. The pedestrian streets were served by an Underground system that has been steadily expanded to five lines since the mid 1970s (U1-U6, excluding U5).

The streets that were not pedestrianized often had trams. That does not mean it was a car-haters paradise however. There were many, many cars, even in the Innere Stadt. The drivers are aggressive. There are some cycle tracks as well, and this is better than Minneapolis, but not as developed as Copenhagen or the Netherlands. There is also a lot of on-street parking. There are not Singapore level prices for auto-ownership, and Vienna remains very German in its appreciation for auto-mobility.

Ringstrasse - 7 lanes for cars.
Ringstrasse – 7 lanes for cars.
Pedestrianized Streets
Pedestrianized Streets

Given the lack of a regular street pattern, a pedestrian wayfinding system would be useful, especially in the areas with lots of pedestrians. More pedestrian streets are being built. Apparently the local merchants complain about construction (understandable) and subsequent lack of access by car (not). Surely there are studies which show sales or rents are higher (or lower) on pedestrianized streets.

While on-street parking is not the worst outcome (it is better than more on-street lanes), it does take away scarce space from better uses. If I were the Emperor of Austria (or even the Mayor of Vienna), I would ban cars in the central areas, where they really are not much needed. Even in the absence of an outright ban, a congestion charge would probably be a net positive for the city. More woonerfs would be good. My term would likely be short.

The Linienwall formed the outer boundary of the second ring. It was replaced by roads. The western part of this is the Gürtel ring road that matches the Minneapolis Interstate ring (The Gürtel is B-221, though the better analog for the Twin Cities is to go from B-221 to B-1, as shown on the map). Railway terminals were built just outside this wall. (We stayed near Westbahnhof).

On-street parking in Vienna
On-street parking in Vienna
Westbahnhof Station
Westbahnhof Station

In particular, crossing the rings on foot is not a pleasant experience. Both ring roads have become traffic sewers (think Lyndale/Hennepin bottleneck, though probably not quite that bad for pedestrians). The railroad tracks also create barriers, with pedestrian bridges periodically, but by no means every block.

While the Innere Stadt is best described as Medieval, a much more orderly ring/radial plan emanates from the Ringstrasse, and while the grid is not perfectly squared as in the Midwest, it is more orderly than in the old city. Vienna respects its architects and planners more than any other city I have seen. Credit for the plan largely rests with Otto Wagner. Andy Nash has a nice history.

In Vienna, you see trams everywhere, they were not dismantled post-World War II as in much of the west. Notably, the Aerial electric wires are now used for recharging battery powered e-buses. Payment is through tickets and validation (on the vehicle), or passes. Tickets are purchased at machines at subway stations — not at Tram stations. Officials there said they have 98% compliance. They thus use Proof of Payment, but don’t enforce much (I estimate 1/1000 trips gets a ticket check from the numbers some Viennese said, but this may be wrong). This speeds boarding radically. The majority of residents have seasonal transit passes.

Housing development rising in Aspern
Housing development rising in Aspern
Lonely, but well-equipped bus stop in Aspern New Town Development
Lonely, but well-equipped bus stop in Aspern New Town Development

The subway system is well used (there were thoughts of dismantling trams post-subway but that did not happen), mostly, though there is a new extension to a planned community we visited (Aspern), which had not yet opened, hence ridership on that line was very low. Presumably this will change over time, but after serving the built-up areas, the infrastructure here now seems to lead the development. Interestingly the station is served by buses which are also mostly empty. One would have thought they would wait on something which does have a high operating cost like buses, but apparently not.

Transit Management Center (for Subway lines)
Transit Management Center (for Subway lines)
The Danube, with Bridge.
The Danube, with Bridge.

Car2Go is popular, as are other carsharing services to lesser extent – but they seem to be station-based. (FYA: Local MSP transit app OMG Transit tells me where nearest Car2Go are in Austria, but not which bus/tram to catch. I believe the market will eventually develop one transportation app to rule them all, but not yet). Locally in Vienna, the App Qando does that. Also Austrian Railways are working on an inter-city ticketing app.)

Supermarkets in-town in Vienna Austria are much smaller than new in-town markets in US, and are of course more widely dispersed (with a smaller selection). This is a better urban model for small apartments with small refrigerators.

You cannot have European transit without European density. Vienna is 414 km2 at 4000 persons/km2 vs. Minneapolis 151 km2 at 2813 persons/km2. Vienna has 1.7 million people overall, while Minneapolis has a just over 400,000. Quantitatively the density of Minneapolis does not appear so much lower than Vienna, it must be remembered that Vienna is a city state in Austria, with large undeveloped areas reserved for park, so the density of the developed area is probably twice the overall density. Vienna’s area is larger than Minneapolis plus St. Paul, though notably smaller than say Hennepin County (1570 km2) with only 1.185 million people. Yet the Twin Cities metro area is larger than Vienna in population as well as area. It is just much more dispersed.

Traveler information at transit stops.
Traveler information at transit stops.
City Bike - Bikesharing in Vienna
City Bike – Bikesharing in Vienna

In short Vienna got the land use and the transit right, but failed to tame the auto and could do better with non-motorized travel. With gas prices around $6/gallon, auto use is certainly lower than the US (currently $3.50/gallon).

As it is a European City, the weather in Vienna is much nicer than Minneapolis on average.



[Flickr photos 1234567]

Starkville, Mississippi

Starkville Airport
Starkville Airport

I visited Mississippi State University, located in Starkville, Mississippi during late April to give a talk. These are my observations.

The airport serving Starkville is shared with the Golden Triangle with West Point and Columbus, Mississippi, and is basically an adjunct to Atlanta, with three flights a day. It is convenient enough, and really small, so there is no need to arrive much before the flight departs.

Starkville Crosswalk
Starkville Crosswalk

Sidewalks are hit or miss, and probably too often miss. While Main Street does have them, as well as a new bike lane to campus, and a transit line (S.M.A.R.T.) running to campus, other streets require pedestrians to walk in the street or along the side of the road. While I understand conceptually complaints about new sidewalks in places which require adjacent property owners to clear snow and otherwise maintain, Mississippi doesn’t get much snow. The problem is either that landowners don’t want to pay for sidewalks (why should they want to?), or they don’t want people walking by their property.

In any event, much of the pedestrian environment looks like this, with the shown ironic marked crosswalk leading to the side of a hill or a mulched planting area.


Main Street
Main Street


Starkville’s Main Street is a classic early 20th century model with a very wide path so that it could store cars diagonally on both sides. While only a few blocks long, it was rented out (one of the advantages of being a college town). It is the County Seat, and thus has a second economic anchor as the home of local government. There is plenty of competition from nearby strip retail centers though.


Cotton District
Cotton District

The Cotton District in Starkville is an area where visionary Dan Camp recreates a number of traditional southern architectural styles, as detailed in this blog post at the Architecturalist. The Rue du Grand Fromage is one of the important examples in this area. The buildings include residential as well as some ground floor commercial activities. I was not aware of this experiment, and was surprised when seeing this collection of buildings emerging out of nowhere.


Mississippi State University campus
Mississippi State University campus

The campus itself has a traditional quad, and the more modern suburban-business park like research center, named for living Senator Thad Cochran (The Thad Cochran Research, Technology, and Economic Development Park). Like the Post Office of yore and the US Board on Geographic Names, I feel things should not be named for the living. At any rate, the park did have a nice automotive research center, including a driving simulator I was privileged to test. As with all such simulators, I am too perceptive to its flaws and thus get nauseous.

The MSU Library is home to the Ulysses S. Grant Presidential Library (surprise), as well as an excellent collection of early 20th century musical devices.

Mississippi State is an SEC school. While the nickname “bulldogs” might not sound too imaginative, (the so-called “University” of Georgia’s team is also nicknamed the “bulldogs”) in fact this is a case of independent evolution, since the names were developed before both teams were joined in the Southeastern Conference (founded 1932), Mississippi State in 1905 (though they were apparently known as the Maroons) and Georgia in 1894.

This matters because the most prominent feature on the campus, and in the town is the stadium. The football club at MSU irons the grid at Davis Wade Stadium, named after an athletic supporter. I could only think of the Wade-Davis bill, which was a proposal for radical reconstruction of the confederacy, of which Mississippi was a part, which likely would have delayed the post-bellum re-ascendency of white southerners by a generation.


It was a good visit. I had never been to the state of Mississippi, and am unlikely to go again any time soon, but it was a pleasure to meet with colleagues and co-authors, some of whom I only knew second hand.

My full set of photos from Starkville is on Flickr.

How constraints drive growth

A city is a positive feedback loop in space.
Why locate anywhere but to be near something or far from something? Cities offer opportunities to be near lots of things (people), and as cities exist, those things must be of value to the people who locate there. By locating, people add to the “stuff” others can reach.
Accessibility is a measure of nearness to things (people), e.g. how much stuff you can reach in x minutes time. Which stuff matters and how much time is acceptable depend on individual preferences, but these can be measured and observed. An area with higher density enables you to reach more stuff in less time because it is physically closer, even if the network is slower (you can move less distance per unit time), provided the density increases at a rate faster than slowness increases.
Some cities are physically constrained, notably San Francisco (a peninsula) and Manhattan and most of New York (islands). In fact, the five densest cities in the US (New York, San Francisco, Los Angeles, Honolulu, and Chicago) all have some significant physical constraints (island, peninsula/bay, mountains/ocean, island/mountains, lake) hemming them in. Not surprisingly, these are among the most expensive cities in which to live. This indicates that the location is especially valuable, because of the accessibility benefits it provides.
Perhaps it is the constraint itself which creates value. Because of the constraint, more people and firms are bidding for scarce space (since the non-scarce non-central available space has a much higher transportation cost (across the bay, off the island, in more distant suburbs) driving up rents. As a consequence, developers build at higher density in the core city, increasing accessibility. Because of the higher density, there is higher accessibility, creating value for residents and businesses, leading to even higher rents. Location has positive spillovers.
A city is a positive feedback loop in space. Spatial constraints accelerate the loop.

Accessibility, Mobility and Density

Are accessibility and mobility complements or substitutes? I have a mental model a graph with a y-axis as density, and x-axis as mobility, where the Northeast corner would be high access: high density multiplied by high mobiilty.
This system behaves differently by modes. For transit, cities arrange themselves on a line from the southwest to the northeast (a positive feedback loop between supply and demand). For auto cities arrange on a line from the southeast to the northwest (a negative feedback loop between congestion and demand). Using data one could place specific cities on the graph. One expects places like New York and Hong Kong in the northeast corner, most US cities in the southeast corner, small developing-world cities without widespread adoption of modern automobile or transit technology in the southwest corner. Depending on where you draw the threshold, it is hard to see too many places in the upper northwest corner, as it would be difficult to grow to have high density without mobility. (Why would the city grow without the accessibility advantages?)
Density Mobility Tradeoff
Accessibility is a good, but it is not a good without costs, and there are limits to how much people are willing to pay for access. It may also suffer from diminishing returns, beyond a point each unit of accessibility is worth less and less. Places like Minneapolis have yet to reach that point, but surely there are places that have.