As urban form is created, through development, redevelopment, zoning decisions, new buildings, and other changes made to the landscape, opportunities to allow for easier pedestrian travel are often missed. Sometimes they are deliberately blocked for seemingly irrational or no reasons. Often developments are built with fences on several sides without any thought of whether it might be good to encourage people to connect through the sides or backs of property.
This map:
View Pedestrian Links near Baileys Crossroads in a larger map
shows a location near Bailey's Crossroads almost right on the border between Arlington and Fairfax Counties. The end of Forest Drive almost touches the parking lot of the apartment building on Jefferson Street (although it's at a somewhat higher elevation). 
The building, instead of installing a staircase that would allow neighborhood people to easily walk from the neighborhood to the shops on Jefferson St., including the Giant Food and Starbucks, blocked it with a fence (see two photos). In the same way, the fence prevents residents of the apartment building from being able to walk around the neighborhood, say to walk their dog or just for enjoyment.
I wonder: who is afraid of whom? Is that apartment building afraid of the neighborhood people? Well, the complex is wide open to Jefferson St.; anyone can just walk in from that side. Are people on one side dangerous and the others not? Or are the neighborhood people afraid that having a link here would allow undesirables into their neighborhood? I can partially see that point of view, although without this pedestrian option, getting to Starbucks requires driving out onto Route 7, which is a royal pain in the neck. Maybe it never occurs to them that they could conceivably walk there if it weren't for this fence.
Just a couple of blocks away, there is a perfect example of just the opposite. It's noted on the above map. Here's a photo of a pedestrian pass-through built into the fence, allowing the apartment complex residents easy access to the nearby shops. This is a really good idea, which I think is probably strongly supported by both the shops and the residents.
I've noted this missed opportunity out in Tysons Corner. Here a large office building abuts a set of shops, but not near the front, but along the side of the building and the back of the shops. This map shows where office workers have worn a path between their building and the shops, which is actually down a steep hill. It also shows how making the same trip via sidewalk (or car) is more than 1/2 mile.
View 2070 Chain Bridge Road Path to Shops in a larger map
It's easy to see that both the office owners and the shop owners would benefit from having this link put in. The office workers would have easy access to more lunch options and services and the shops and restaurants would have a larger market. It's a no brainer, but I suspect no brains have given it any thought.
There are certainly thousands of these small linkages that could be unblocked or created. Each one might open up pedestrian opportunities to a few people or a few score of people. But all multiplied together one could imagine literally thousands of short car trips being eliminated and quality of life for those people improved.
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Steve Offutt of Arlington likes to look for shortcuts
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