1 region · 2 sites · down to 40 m (131 ft)
Northern Mariana Islands
- Regions1
- Sites2
- Max depth40 m (131 ft)
In the Northern Mariana Islands you dive caverns with daylight, not caves in the usual sense. On Saipan you walk down 112 steps to the Grotto, a collapsed limestone cave with three openings to the sea and usually more than 30 m of visibility; off Rota you drop with a dive operator into the grotto of Rota Hole (Senhanom Cave), where sunlight falls through the roof in columns. The water is 27–29 °C all year. Rota is reached by a small plane from Saipan or Guam.
Not to be missed
- The Grotto (Saipan) →
A shore dive into a collapsed cave with three openings to the sea; according to AFAR one of the best cavern dives in the world.
- Senhanom Cave (Rota Hole) →
Columns of sunlight through the grotto's roof, at their finest from March to October; by boat with a dive operator on Rota.
Regions
Map
Good to know
- Rota has no recompression chamber; the nearest is the US Navy's on Guam, half an hour's flight away. A working chamber on Saipan is not confirmed.
- On Rota there is no nitrox and no technical diving; the operators pick the sites on the day, by weather, sea and your experience.
Tips for safe and enjoyable diving
- In the Grotto: keep enough gas to swim back underwater and make your safety stop inside. Outside the cave getting back in is often impossible and there is no exit; go outside only with a guide.
Certification requirements, configurations and trimix depths are estimates for planning. Always check them locally and dive within your training.
News
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