Roi-Namur is the northern-most island in the Kwajalein Atoll (see map). A twin-prop plane makes a couple of daily trips between Kwajalein and Roi and, if seats are available, you can fly for free. Many people from "Kwaj" head up there for a day or two of relaxation; not only for the secluded beaches but also for the 13+ channels of cable TV (compared to the 8 offered on Kwajalein).

Roi-Namur is also the location of many optical and radar missile tracking equipment, including the ALTAIR (ARPA (Advanced Research Project Agency) Long-Range Tracking and Instrumentation Radar) and ALCOR (ARPA Lincoln C-band Observable Radar). These radars are used to track ballistic missiles and space objects out to and beyond synchronous orbit.