The Grotto

Northern Mariana Islands, Saipan, Mariana Archipelago, United Statescave22 m maxintermediate

Conditions & tides

Satellite view of The Grotto

The GrottoSaipan

Rough · 2/5

© Esri

conditions visualisation

Rough2/5

Rough at the surface right now — rough all day, no calm window.

Wind16 kn ENE

Current~0.6 kn NW · model

Swell

1.5 m · 7s · ENE

Water

29 °C

Max depth

22 m

Conditions through the day

6 AM6 PM

Calmest current near slack — 12:30 & 01:15 local

Sunrise 06:15 · Sunset 17:45 local

Show details

Tide · local

Outlook — select a day for full conditions

On-face swell 1.6 m — the component of the swell aimed at this site’s exposed face. Current is a regional model value (Copernicus, ~9 km grid) — a guide to the area, not a precise reef measurement. Imagery © Esri · not depth or visibility.

Scored by DiveConnect's site-physics model

Marine forecast via Copernicus Marine. Score is a rule-based guide from swell/wind vs. the site's exposure — always dive your own assessment.

Dived here today? How were conditions vs. what we showed?

About this site

The Grotto is a collapsed limestone cavern on Saipan, reached by a long flight of steep steps. Divers and snorkelers can jump into the cobalt-blue lagoon from a large natural rock and explore the cavern and its swim-throughs.

Three holes in the rock wall open to the ocean, letting a glowing blue light into the cavern. The largest hole gives an exceptional photo background. Winter brings rough waves, and the site is dived at 22 m maximum.

AI-written site guide

Marine life here

Confirmed by our research team, reported by independent divers, or observed nearby via iNaturalist — each entry is labelled with its source.

Princess DamselPomacentrus vaiuliReported here · unconfirmed
Dusky SurgeonfishAcanthurus nigrofuscusReported here · unconfirmed
Arc-eye HawkfishParacirrhites arcatusReported here · unconfirmed
Fivestripe WrasseThalassoma quinquevittatumReported here · unconfirmed
Leptastrea purpureaReported here · unconfirmed
Pacific Orange-spine UnicornfishNaso lituratusReported here · unconfirmed
Reticulated DamselfishDascyllus reticulatusReported here · unconfirmed
NudibranchNudibranchReported here · unconfirmed
TrevallyTrevallyReported here · unconfirmed
Napoleon (humphead) wrasseNapoleon (humphead) wrasseReported here · unconfirmed
BarracudaBarracudaReported here · unconfirmed
Blue DragonPteraeolidia semperiObserved near here · iNaturalist
Spotted TobyCanthigaster solandriObserved near here · iNaturalist
Green Sea TurtleChelonia mydasObserved near here · iNaturalist
Threespot WrasseHalichoeres trimaculatusObserved near here · iNaturalist

Diver notes

Durable tips from divers — access, hazards, marine life, facilities. For day-of conditions, use the report tool in the conditions card above.

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