Where: Dug into the bank, beside the feeder creek for the local swamp.

What: Tunnels with rooms off to the side with hessian bags filled with leaves stung between 4 posts for beds, A dining room with enough tables and chairs to seat everybody, Outside would be a Earth bridge rigged with explosives for defence with a pipe and water turbine built into it to generate electricity and a windmill to pump water into the compound through a filter beside it plus numerous defences and a kitchen plus a long drop which has dirt sprinkled over the dirty stuff and farms between the bank and the creek.

Who: Mates, Family who else?

Supplies: whatever I can get me hands on metals, tools, materials, ammo, guns, anything I could fit in there. Plus food.

Construction: Earth, Timber, metals, concrete whatever I can get a hold of.

And A Bit of both above ground and below ground.

Map: The other areas created in the maze-y looking part are passages/ rooms.
The obstacles would be abatis in front of covered pits with wire entanglements on either side you would get over them laying down ramps that have been built move the abatis then proceed. And at the end of the pipes and at the tank would be taps for water use.