It was the first Gap Filler site in the nation.
In addition to the main facility, Empire operated two AN/FPS-18 Gap Filler sites:
In addition to the main facility, Richmond operated three AN/FPS-18 Gap Filler sites:
All three Gap Filler sites remain with both the radar towers and support structures intact.
In addition to the main facility, Walker operated several AN/FPS-14 Gap Filler sites:
In addition to the main facility, Houman operated an unmanned Gap Filler site:
In addition to the main facility, Z-129 operated several unmanned Gap Filler sites:
In addition to the main facility, Charleston operated two unmanned Gap Filler sites:
The other two Gap Filler sites have been obliterated and redeveloped.
The three Gap Filler sites have their support buildings still standing, also abandoned.