Roi-Namur

Roi–Namur Battlefield
Roi-Namur
LocationKwajalein Missile Range, Kwajalein Atoll
Coordinates9°23′46″N 167°28′33″E / 9.39611°N 167.47583°E / 9.39611; 167.47583
Built1944
NRHP reference No.85001758
Significant dates
Added to NRHPFebruary 4, 1985
Designated NHLDFebruary 4, 1985

Roi-Namur (/ˌrɔɪ nəˈmʊər/ roy nə-MOOR) is an island in the north part of the Kwajalein Atoll in the Marshall Islands. Today, the island is a major part of the Ronald Reagan Ballistic Missile Defense Test Site, hosting several radar systems used for tracking and characterizing missile reentry vehicles (RV) and their penetration aids (penaids).

Roi-Namur is a military base of the United States, leased from the Republic of the Marshall Islands; however, defense of the Marshall Islands is the responsibility of the United States through the Compact of Free Association.

In 2024, a flooding event caused by wave overtopping made national news in the United States, with dramatic footage of water bursting through a door.