In many parts of the world it's common for people to walk a lot. Sometimes they'll walk long distances - hours, days - to get where they need to go. It used to be pretty universal.
When I was younger I thought this just happened, that you could get up and start walking and just spend the night wherever you wound up. I was disappointed to discover that there are large sections of the country that are really very inhospitable to people on foot. To a large extent, it's because major roads have been built for cars with almost no thought to pedestrians. Outside of towns and cities, sidewalks are scarce, shoulders are narrow, and speeds are high. In some places, pedestrians are harassed, particularly outsiders.
My first reaction was to praise long-distance trail projects, like the Appalachian Trail or the Pacific Coast Trail. Certainly, people do take long walks on these trails, and they're great for spending time in nature, getting exercise and seeing pretty mountains. But if you've ever hiked on them, you'll know that they're not very practical for actually getting anywhere. They usually don't go through population centers: Harper's Ferry, West Virginia is one of the few towns that are actually on the Appalachian Trail.
The first reason for that is that land in towns is expensive, and walking trails didn't provide a good return on investment for either private companies or governments to spend the money to develop them. The second is that they piggyback on existing trails, many of which were made for visiting mountaintops. While it's great for hikers to climb Bear Mountain on their way through the Hudson Valley, it's not really the most convenient route to get from, say, Peekskill to Middletown.
I developed an interest in stories about people walking long distances, and looked for older ones that went back before all those roads were built and filled with cars. It turns out that in a lot of circumstances it wasn't much easier to get around on foot. There were weather problems, brigands, lack of food and difficulty finding or affording places to stay. There were also difficulties such as not having a good path to travel or losing the path.
One thing that's very striking about these narratives, particularly the more recent ones, is how many times the walkers get into cars, buses and trains. Especially cars. Five hundred years ago, if someone walked from Paris to Brussels they'd have had to walk from inn to inn, and once they left home they wouldn't see their families until they came back. Today, Appalachian trail hikers regularly hitch rides to grocery stores, or get visits from family members in cars. Just about every trail journal has an entry about getting a ride to a campsite further down the trail and then hitching another ride back to complete the skipped section.
What I learned from these stories is that walking too requires infrastructure. The paths and maps need to be created and maintained. There need to be bridges or boats to cross rivers and other obstacles. There need to be places to obtain food and places to stay, and they need to be affordable to walkers. This is a lot of work, and down through the ages it's something that people have spent years setting up. This infrastructure doesn't just happen.
The reason I've been talking about this stuff is that I feel it's very important to be able to walk just about anywhere we want to go. Not that the government should immediately go out and build straight, level walking paths for every city pair, with subsidized travelers' inns every five miles - although that would be a better use of the stimulus money than half the projects that are currently begging for it - but that we should aim ourselves in the general direction of making it easy to get places on foot, between towns as well as within them.
It's actually quite a tragedy that country roads used to be places where people could walk, and they still are to some extent, but with the number and speed of cars these days I wouldn't want to spend a month walking along them. When I was a kid I once visited coastal villages in Italy and Greece, and one thing that impressed me so much - impresses me to this day - is how they had well-maintained footpaths to other villages. I'm talking paths paved with stone, but too steep and narrow for cars. They were much more direct than the roads, because they didn't require all the hairpin turns. They weren't hiking trails or rail-trails or carriage roads. They were footpaths, built for people to get around.