On paths and in open spaces we linger along edges. This is so true it is called “the edge effect.” People congregate along whatever borders a walkway or space—building fronts, hedges, fences, tree rows.
As a result, a critical difference among paths and neighborhoods is the amount of edge they offer walkers. How different we feel walking through an open field than along a hedgerow.
How little edge modern suburbs and commercial strips offer with their buildings surrounded by swaths of lawn or parking compared to older neighborhoods and downtowns fronted on every block by homes and businesses.
How many edges have been lost to the 25- or 50-foot front setback?
We seek out edges for many reasons. They offer a back we may be able to lean on, a retreat from activities in the open space, and protection from the weather.
Niches enhance the edge effect. They offer more surfaces to lean on and look at, more protection, a less visible lookout, and a quieter place for phoning or talking. Along building fronts, they connect public to private life. Only edges, and especially alcoves, offer refuges with prospects and a choice between kinds of activity.
Any hint of a recess—any jog in a facade, any pocket in a hedge—attracts more people, more lingering, but the most effective niches provide strong sides and back with an overhead canopy. Recessed doorways can be niches, but they can cause conflicts between those standing and those entering and leaving so attractive building fronts should be designed with recesses other than doorways.
Because the edge border is seen up close, its surfaces should offer engaging details. Because it is within reach, its surface should offer engaging texture. A natural edge tends to automatically offer interesting, touchable features at the smallest scale, so the greater design issue is providing them on a built edge.
Frequent niches make facades irregular or articulated, the kind that urban experts like Whyte, Alexander, and Gehl have found “particularly attractive places for staying.” As a consequence, smooth facades are one of the greatest costs modernist architecture has imposed on people outdoors.
Meanwhile, water with its intimate association with our bodies and our survival always attracts us so land/water edges form major destinations everywhere. In recent years, cities around the globe have begun reopening long buried stream channels, creating opportunities for spectacular waterside walkways enlivening entire neighborhoods.
Gehl reports that reopening the river through Arhus, Denmark’s second largest city, has made it “the most popular space in the city.” People crowd its banks in good weather, and shops have proliferated along its edges. He also reported that “Real estate prices along the river are also among the highest in the city.”