Tokyo’s extraordinarily long recreational paths

Like Japan’s other coastal urban areas, the Tokyo region is crossed by several large rivers, among which the most important are the Ara (Arakawa 荒川), the Edo (Edogawa 江戸川), and the Tone (Tonegawa 利根川) east of the city and the Tama (Tamagawa 多摩川) to the south. These rivers have been the source of Tokyo’s water since the city’s founding. They have also been responsible for numerous floods, some of which have caused tens of thousands of deaths and an enormous amount of property damage. Attempts to control the rivers go back many centuries. The Tone, the largest and once the most destructive of the rivers, flowed to the sea mostly through what is now the Edo River as late as the 17th century, when it was largely diverted to pass through less populated areas to the east. The Ara reached Tokyo Bay through what is now known as the Sumida River (Sumidagawa 隅田川) in central Tokyo until the early 20th century when it too was mostly diverted to a parallel riverbed in what is now eastern Tokyo. Since the late 19th century, all of the rivers have been dammed at numerous points upstream and acquired substantial levees or (in their most urban portions) concrete walls over much of their length. Parts of the lower Ara, Edo, and Tone now flow through mostly artificial channels created by bulldozers. Recent work has centered on making these channels at least look natural.¹

The rivers’ levees began to be used as informal footpaths long ago. Since the early 1980s, these paths have been transformed into formal recreational trails, as bicycling, running, and more or less serious walking have become as important in Japan as in the rest of the modern world.

A large swath of the Tokyo region highlighting pedestrian facilities and rail transit lines. “Pedestrian facilities” segments shorter than 30 m have been eliminated for space reasons; this mostly takes out short alleys and bridges over major streets. The classification of rail lines needs a bit of explanation. The distinction between subways and regular passenger rail lines in Tokyo is mostly a question of who runs the line. Many subway lines in Tokyo extend for some distance along suburban railroad tracks, and most rail lines operate at rapid-transit frequencies in central Tokyo. Note that the fully grade-separated Yurikamome and Rinkai lines, as well as the monorails in Tokyo, Tama, and Chiba, have been classed as subways even though they are not managed by either of Tokyo’s two subway companies. The map also shows northern routes on the Yokohama subway. GIS data are mostly from the Geofabrik version of OpenStreetMap, all heavily edited. Edits include the excision of railroad yards, freight-only lines, and all but a single track on lines in the central city. It’s possible that some freight-only lines have been left near the map’s edges.

I have not been very successful in documenting this transformation process, perhaps because it’s always played second fiddle to the work of flood control. What’s clear is that building and improving the trails has been going on for forty and more years and that in many cases it’s been local jurisdictions that have been responsible for it. Because of the timeline and because the rivers all pass through numerous jurisdictions, the trails have not been constructed in a very consistent way. Some are wide, some narrow. Some are paved, some are not. Sometimes there are trails both on the levee and down on the floodplain, sometimes in just one of these places. In certain stretches, there are trails on both banks, elsewhere just on one. In many cases, carefully graded paths take users under bridges; in other cases, users have to cross roads or take stairs. Where there are wide floodplains, parks have often been established, and various amenities—baseball fields, tennis courts, benches, and bathrooms—have been added; sometimes, however, the trails are just about the only improved parts of the rivers’ rights-of-way.

View across the Edo River near Ichikawa, one of the places where the entire floodplain has been repurposed for recreational uses. Photo was made from a trail along one levee; a levee trail can be seen on the opposite bank, in the distance. Down below is a trail on the floodplain, as well as athletic fields. The trail on the floodplain continues under the bridges. It’s connected to the levee trail by graded pathways.

Narrow sections on the trails along the Tama River in Ota. The buildings in the background are in Kawasaki. The road on the right is at a lower level than the levee.

The trails also differ in the extent to which they’ve been “branded.” The trail along the Tama, for example, has much more consistent kilometer markings than the trails along the Edo and Tone. It’s also more likely than the other trails to have signs offering friendly warnings about certain obvious dangers, such as bicycle/pedestrian collisions (all these trails allow cyclists).

Sign along the Tama River trail.

Despite these differences, the trails have become usable over enormously long distances. The trail along the Ara is 68 km long, that along the Edo goes on for 60 km, and the one along the Tama is at least 50 km in length. (The much less urban Tone trail has stops and starts and would be harder to follow for a substantial length.) Of course, it’s not surprising that the world’s largest urban area should have some the world’s longest urban recreational paths, but Tokyo is not generally known for its recreational facilities, and the trails, which have become one of Tokyo’s most distinctive features, have not been widely publicized.

All of these trails get a fair amount of use, at least where they aren’t too far from settled areas. It was pouring the day I visited the Ara River trail, and there were still numerous runners and cyclists using it; there were even baseball players on the athletic fields.

Along the Ara River trail on a wet and windy day. Most users were staying on the path down on the floodplain. The levee path (right) was uncomfortably windy.

The river trails are chiefly recreational trails. The rivers the trails parallel are rarely natural routes for commuting or shopping. Tokyo is definitely a multi-nodal urban area, but most of its nodes are relatively close to the traditional city center. The most heavily traveled transport links in the Tokyo area tend to be focused on the center, and are usually perpendicular to the trails. Also, because of the flooding problem, the older towns that often became the commercial centers of what is now suburban Tokyo tended not to be close to the rivers, and the river paths naturally don’t take you to these places.² The fact that some of the “rivers” now flow in courses that are at some distance from their original bed often brings them even further from traditional settlements. No doubt a few commuters and shoppers do use the trails, but I suspect they’re not numerous. I didn’t see anyone carrying a shopping bag in the many kilometers I walked these trails in July. There does not seem to be any serious movement in Tokyo urging the building of a more complete network of trails that would include routes between the suburbs and central Tokyo. The recreational trails along rivers constitute a large proportion of Tokyo’s off-road pedestrian facilities.

The recreational corridors that include the trails are clearly quite different in character from most of Tokyo, where smallish houses and other structures typically occupy a very large proportion of available land. The corridors, in contrast, seem extraordinarily open, especially those along the man-made river channels, which can be a kilometer wide. It’s quite startling to see them from train windows, where the contrast between densely built-up city and brief episodes of openness seems particularly vivid. Because these areas are distinctive and attractive, numerous moderately expensive high-rise apartment buildings have been built along some of the corridors even though the neighborhoods in which they are located are not on the whole particularly fashionable places. Although Tokyo, like other Japanese cities, is generally less segregated by class than most Western cities, much of eastern Tokyo in particular is perceived as being rather blue-collar in character. Thanks to the recreational trails, many areas have undergone a modest amount of gentrification.

Apartment buildings along the Tama River trail, Ota.

The Sumida River which adjoins central Tokyo has also acquired a recreational path, but the path has a somewhat different history and character than those along the Ara, Edo, Tone, and Tama.

Pedestrian facilities and rail transit lines in central and part of eastern Tokyo. See notes on map above for information on data. In this map, even the shortest “pedestrian facilities” have been included.

Unlike most of the longer rivers, the Sumida (or anyway its lower half) is essentially a tidal inlet off Tokyo Bay. There is no floodplain for athletic fields along the lower Sumida, and there are no levees. There are concrete walls that serve the same purpose as levees, but of course these could not be transformed into paths in the way that the levees were. Also, because the lower Sumida runs through central Tokyo, its banks were much more likely to be lined with industries than the banks of the longer rivers, especially where the river flowed into the Bay, past more or less man-made islands. (The upper Sumida River—roughly, north of Shirahige Bridge—has levees, and the path along the Sumida here seems to have roots very much like those of the longer rivers; it’s in part a byproduct of flood control measures.)

Unlike the paths along the longer rivers, the path along the lower Sumida had to be designed as a pedestrian path, and it only came into being in the early 21st century. Building it wasn’t particularly easy, since, in most cases, substantial landfill along the river was required, and also, because some of the bridges across the river were not very high, tunnels below the high tide mark had to be dug. Also, a decision was made to do some serious landscaping along much of the Sumida Terrace; this must have complicated its construction. This construction in fact is still underway, and some gaps in the path remain, but alternate routes are pretty clearly marked.

The path along the Sumida also differs from the longer trails in that it’s been given a formal name: it’s the Sumida River Terrace (Sumidagawa terasu 隅田川テラス). In addition, it’s acquired much more consistent signage than the longer trails as well as a carefully designed series of maps that are posted every hundred meters or so.

One of the many maps along the Sumida River Terrace.

The Sumida River Terrace (or at least its southern portion) differs from the longer trails in one more way: It does not permit cyclists. It also has many more benches. You certainly see runners there, but the Sumida River Terrace wasn’t really set up to be an athletic facility; it was designed to be a place for relaxing and for enjoying the urban landscape.

I can’t prove it, but I suspect that urban rivalry was a factor in the Sumida River Terrace’s construction. The people who govern Tokyo are well aware that it’s in competition with places like New York, London, and perhaps Shanghai for “world-city” status and most certainly became familiar with thriving urban features like Hudson River Park, the Brooklyn Heights Promenade, and the pedestrian paths along the Thames and the Huangpu Rivers, which made Tokyo’s once run-down and hard-to-access waterfront seem something of an embarrassment. The Sumida River Terrace is intended to be “globalized” Tokyo’s elegant inner-city waterfront walkway.

The Sumida River Terrace appears to be a success, at least on weekends and late afternoons, when there are numerous users (including many more foreigners than on the longer, further-out trails). It’s certainly contributed to the slow gentrification of the neighborhoods along its banks, which, traditionally, were rather working-class.

The Sumida River Terrace on a busy weekend.

The place can be rather empty at other times, however, when the homeless people who live on some parts of the Terrace become a major proportion of its users, especially on the East Bank, where there are some permanent-looking encampments. Another issue is that much of the East Bank and a small part of the West Bank of the Sumida are shadowed by a noisy expressway. The expressway does provide some shelter from sun and rain, but this makes it all the more attractive to the homeless.

The Sumida River Terrace, and the longer paths along the Ara, Edo, Tone, and Tama Rivers (and several shorter paths along waterways elsewhere in the urban area) nonetheless do constitute a relatively new and generally appreciated feature of Tokyo’s urban landscape. Like their counterparts in North American, European, and a small number of Asian cities, these paths are intended to be a kind of haven from the automobile- and transit-dominated city surrounding them, a place where long-distance movement on foot and (in most cases) by bicycle is convenient and pleasant. Of course, like other recreational paths in cities all over the modern world, these paths are so completely separated from roads for automobiles and so oriented to recreational use that they do not really challenge automobile hegemony either.