The Nautilus UnderSea

The UnderSea is a classic and beautiful small ship catering to small groups of only 18 divers. Many divers know her from her previous life as the Undersea Hunter of Cocos Island fame, but with massive upgrades including lengthening by 20 feet, a new superstructure, an enclosed dive deck and a host of other improvements, it is hard to recognize the original ship. The special feature of this ship is intimate group size combined with Nautilus spaciousness and luxury.


Triple Stateroom


Main deck. 2 bunk beds, with 1 of the bunks for extra storage. Ensuite with private shower and individually-controlled air conditioning.


A, B, C, D, E, & F

Lower deck. Upper and lower beds. Configuration varies between the 6 staterooms. Ensuites with private showers and individually-controlled air conditioning.

ADA Compatible Stateroom


Adjacent to the dive deck. Wheelchair friendly. Twin beds. Huge window! Ensuite with private shower and individually-controlled air conditioning.

Premium Suite


A large premium suite on the sun deck can be configured into two full beds or one large bed. Flat screen TV, multiple windows, ensuite, plenty of storage space, individually-controlled air conditioning and easy access to the hot tub.


Clean and shiny bathrooms are found onboard the Nautilus Under Sea
Bathrooms with showers in all suites and staterooms.
Wifi is available onboard all three vessels
Internet via Wi-Fi
the Egyptian cotton sheets cover comfortable beds onboard the Nautilus liveaboards


  • 105 ft long, 24 ft beam
  • USA shipyard built
  • Stabilized
  • ISM safety certified
  • 18 guests, 9 ensuite staterooms and suites
  • Internet access & satellite phone
  • Caterpillar engine power
  • Air fills, nitrox, rebreather friendly
Sun Deck

Sun loungers, al fresco lounge, bar, hot tub and premium suite.

Click on highlighted room to view image

Main Deck

Main lounge and dining room, dive deck, water level platform, ADA compatible stateroom, and triple stateroom.

Click on highlighted room to view image

Lower Deck

6 staterooms on the lower deck.

Click on highlighted room to view image