Olke has Barricades along the streets, and a Military Tent on the eastern side of the town. Olke is a popular spawn location, so more than likely you'll find one or multiple players roaming around looking for gear to start off with, or more experienced players stopping en route to Kin or the Abandoned Mine.
There is a variety of loot that spawns, mainly Civillian and sometimes low-to-mid tier Military.
There is also a bunker near Olke, fittingly called the Olke Bunker.
Inside the town, here is a brown house with the words "IT GOT ME" written in blood on one of the walls, presumably by Patient Zero.