USS Gilliam - Bikini Atoll

57m Max

25-45m Vis

liveaboard

Site Overview

USS Gilliam is one of the most celebrated dive sites in Bikini Atoll, an attack transport sunk in 1946 at 55 m, one of the few fully-intact amphibious assault ships in the fleet, an advanced technical dive. The site is defined by an attack transport sitting at 55 m, one of the few fully-intact amphibious assault ships in the Bikini fleet, creating an underwater landscape that rewards divers with every visit. The large hull attracts schooling fish, groupers and the occasional grey reef shark in the blue. Water clarity in this part of the Marshall Islands is frequently excellent, with visibility often extending well beyond 25 metres and a comfortably warm tropical temperature year-round. The combination of healthy hard and soft corals, nutrient-rich currents and sheltered reef systems makes USS Gilliam a reliable location for both macro photography and wide-angle encounters. Local dive operators run regular trips to the site from nearby bases, and the geography means conditions are suitable across a range of experience levels with appropriate guidance. Conservation is taken seriously throughout the Marshall Islands, and USS Gilliam benefits from marine protection that keeps fish stocks high and coral coverage dense. Divers who plan their visit around the calm season will find the most predictable conditions, though the site can be enjoyed throughout the year. USS Gilliam deserves a place on any serious Pacific diving itinerary, offering a genuine taste of the untouched beauty that makes Marshall Islands diving so highly regarded internationally. Regular visitors note that the marine life here, including giant grouper, grey reef shark, soft coral gardens, bigeye trevally, humper red snapper, giant moray eel, makes every descent memorable.

Dive Briefing

"The dive at USS Gilliam begins with a controlled entry and a short transfer from the nearest base, with the guide giving a full briefing on the site layout, expected marine life and emergency procedures. Descending toward an attack transport sitting at 55 m, one of the few fully-intact amphibious assault ships in the bikini fleet, divers are immediately surrounded by giant grouper, grey reef shark, soft coral gardens, bigeye trevally, with the reef revealing more detail the closer you look. The maximum depth reaches about 57 metres, while the average depth sits near 54 metres, so gas planning and a dive computer keep the profile safe and comfortable. Currents are described as mild, and the guide chooses the entry time to make the most of slack or mild flow, using a reef hook or DSMB when needed. The topography offers natural swim-throughs and ledges that shelter larger animals, and the open water above the reef often holds cruising pelagics. Throughout the dive, neutral buoyancy protects the fragile coral, and the group stays close to the guide to manage depth and any surge. The safety stop is completed in open water on a DSMB, and the boat follows the bubbles to collect divers at the exit point for a relaxed return to base. Descend along the intact deck on a calm morning, conserving gas for the deep deco obligation"