The Two Safehouse Types, Player Created (Green) and NECRA Created (Blue)
There are two categories of safehouses in WotLD: NECRA-created safehouses and player-created safehouses.
Safehouses are the only location where Fear, and Fatigue can be recovered and are also a place where Health is regained. Staying in a safehouse also protects you from hostile players and zombies. (See Raiding for exceptions.)
Until you reach Level 4 you can only use NECRA Safehouses. These have been placed throughout the area to allow survivors to access them.
From level 4 you can create your own safehouses. These have several advantages over NECRA safehouses, but cost Survival Points to create, and must be maintained by one or more guards. Survivors on guard duty will only recover at half the normal rate. Player built safehouses can be placed anywhere, allowing you to keep your survivors safe and rested no matter where you go, you just have to be careful because you can also be attacked by other members while your characters are building the safehouses. See the player-created safehouses section for more detailed information.