Philadelphia has an underground pedestrian concourse in center city. It is, however, not clean, well lit, nor as actively policed. In some alternate timeline, the stalls would be filled with shops, and it would be a great alternative to walking the streets when it's too hot, too precipitous, too cold. But we struggle to even keep our public transit system funded, let alone something like this, which is a shame.

I hope I live to see Philadelphia's infrastructure get rehydrated with some of that GDP it generates for the rest of the state, and region.