> If this idea were viable, someone somewhere in the world would have already done it.

Hong Kong does this in the downtown area. It’s viable because of the very high population density and prevalence of foot traffic.

https://duckduckgo.com/?q=hong+kong+pedestrian+bridge&iax=im...

Many cities in fact already have it. We call them skyways. The bridge is building to building. It is generally not on the corners, but in the middle of the block. Getting in is tricky because you need to find the elevator in the middle of the building, but once in you don't leave for a while so that isn't a big deal.

Yeah, I'm aware of what skyways are. And there's no city in which they remotely come close to covering as much walking territory as sidewalks do.

True, but they do cover most of the areas where a large number of people want to be often.

Downtown Manila basically has bridges over every intersection, or underground walkways with elevators for the disabled.

It works out great. Though admittedly it’s more of a workout than walking in flat Manhattan.

So you've got to go up and down to cross every single intersection? That sounds like a nightmare that makes walking take significantly longer.

It works because driving is so inconvenient there.

If driving is already so inconvenient why not just relegate it even further and prioritize walking over vehicles at intersections? Why should all the larger numbers of pedestrians be forced to take much longer to get where they're going on account of all these bridges to benefit a smaller number of vehicles?

Sure, improvements should be made. The pedestrian bridges themselves are improvements. People use them by choice, and not because they appreciate the exercise. It would be easy to underestimate just how many many vehicles and pedestrians are attempting to navigate the metro Manila area. Roads and other transit infrastructure are seriously lacking in Philippines, relative to that seen in more "developed" nations.

they actually do this in places like Minneapolis. mainly because it's just too cold to be outside for prolonged periods in the winter. my friend walks almost his entire commute without going outside.

Yeah, so that system is only 9.5 miles, and claims to be the largest such system of connected aerial sidewalks in the world. Meanwhile, NYC has 12,750 miles of sidewalks.

That's a several orders of magnitude difference between the capacity of the two systems.