[2021] Best POI base

I don't need a lot of space for a single player base. But I want the strongest materials possible, and I like to be up off the ground. I also don't want to worry about sleepers. Accordingly, I find the concrete building remnants the best option among existing POIs. Since they tend to appear in town across the street from each other, I've also taken to making bridges to connect multiple of these remnants, mostly to open up places to escape if the primary site of the base is compromised.