Layer 8

PowerPoint was my first thought too, but there are a few transitions in the middle that I didn't think you can do in PowerPoint (when the balloon pops for example).

The rest of the animations are quite simple, technically.

We have two nearby tunnels. They'll be packed now. But hazmat trucks and larger oversized vehicles can't go through tunnels. There's also a longer way around the northwest of the city, but that'll be crowded now too. That's where everyone lives. The bridge over the river was the interstate trucking corridor from DC to Philly up to New York and Boston.