There are VHF repeater chains, AX-25, and other fancier ham infrastructure, but if that's up and running, the cellular network is probably up, too.
The next ARRL Field Day is June 25-26. This is supposed to be practice for emergency communications, but it's really just a DX contest. Everybody just tries to contact other stations at random; there's no attempt to set up a net.
You'll see antennas in parking lots. Visit the people there and see what they're up to.