Iro Maru Wreck Palau - Rock Islands
The Iro Maru is one of those wrecks we always make time for when we're in Palau, especially if we have newer divers in the group. It’s a 143-meter oiler, sunk during Operation Hailstone in 1944, sitting upright on the seabed at a comfortable 27 meters. What we really love about the Iro is its sheer accessibility and how much there is to poke around in without needing advanced certs. You can swim through the superstructure, peer into the engine room, and even pop down into the cargo holds if you're comfortable. Light filters in through bomb damage and open hatches, illuminating schools of glassfish that swirl like silver clouds. We've seen moray eels peeking from pipes, schools of batfish circling the mast, and robust lionfish perched regally on decks. It’s an almost perfect introduction to wreck diving, with plenty of intact structure to explore and a fascinating history you can practically feel. The bow gun is always a highlight, a really stark reminder of its past. We’d suggest going in the morning; the light penetration can be magic.
- Location
- Rock Islands, Palau, Central & South Pacific
- Coordinates
- 7.294800, 134.421200
- Type
- wreck
- Maximum Depth
- 27m
- Difficulty
- Beginner
Marine Protected Area: Koror Southern Lagoon
Best Time to Dive in Rock Islands
The warmest water temperatures in Rock Islands occur in October, averaging 30.0°C. The coolest conditions are in February at 28.4°C.
Monthly Water Temperatures
- January: 28.8°C
- February: 28.4°C
- March: 28.8°C
- April: 29.3°C
- May: 29.8°C
- June: 29.9°C
- July: 29.8°C
- August: 29.7°C
- September: 29.9°C
- October: 30.0°C
- November: 29.9°C
- December: 29.6°C
Nearby Dive Sites in Rock Islands
- Big Drop Off - 20-40m (wall)
- Blue Corner
- Blue Corner (and Blue Holes)
- Blue Holes
- Chandelier Cave (cave)
- Chandelier Caves - 34m to 98m
- Chuyo Maru (wreck)
- German Channel - 21m (drift)
- Helmet Wreck - 34m to 98m (wreck)
- Iro - 16-131ft (5-40m) (wreck)
- Jake SeaPlane (wreck)
- Jellyfish Lake - Ongeim’l Tketau - 12m
- Lighthouse Channel (drift)
- Mandarinfish Lake - 16-131ft (5-40m)
- MT ARAYAT - 0m (wreck)
Nearest Dive Centres to Iro Maru Wreck Palau
Marine Life in Rock Islands
Home to 198 recorded species including 171 reef fish, 15 sea cucumbers, 4 clams & mussels, 4 sea snails & nudibranchs, 2 starfish, 1 sea urchins.
Notable Species
- Boring Clam (Tridacna crocea) - Clams & Mussels
- Small giant clam (Tridacna maxima) - Clams & Mussels
- Black sea cucumber (Holothuria atra) - Sea Cucumbers
- Orange-lined Triggerfish (Balistapus undulatus) - Reef Fish
- Pinkfish (Holothuria edulis) - Sea Cucumbers
- Saddleback Butterflyfish (Chaetodon ephippium) - Reef Fish
- Greenfish (Stichopus chloronotus) - Sea Cucumbers
- Bristle-toothed Surgeonfish (Ctenochaetus striatus) - Reef Fish
- Burrowing urchin (Echinometra mathaei) - Sea Urchins
- Bullethead Parrotfish (Chlorurus sordidus) - Reef Fish
- Tigerfish (Bohadschia argus) - Sea Cucumbers
- Threadfin (Chaetodon auriga) - Reef Fish
- Telescopefish (Epibulus insidiator) - Reef Fish
- Banded Goatfish (Parupeneus multifasciatus) - Reef Fish
- Kihikihi (Zanclus cornutus) - Reef Fish
- Banded maori wrasse (Cheilinus fasciatus) - Reef Fish
- Sunburst Butterflyfish (Chaetodon kleinii) - Reef Fish
- Curryfish (Stichopus vastus) - Sea Cucumbers
- Butterfly fish (Chaetodon vagabundus) - Reef Fish
- Honeycomb Grouper (Epinephelus merra) - Reef Fish
Recommended Packing List for Iro Maru Wreck Palau
Based on average water temperature of 29.5°C, currents 13 cm/s.
- Shorty or Rashguard - warm 30°C water needs minimal exposure protection
- Mask - essential for every dive
- Fins
- BCD - buoyancy compensator
- Regulator - your most safety-critical piece of gear
- Dive Computer - tracks depth, time, and NDL
- Surface Marker Buoy (SMB) - essential for boat pickups
- Dive Torch - useful for crevices and colour at depth
- Underwater Camera - capture your diving memories