MJ Murphy Ltd - Aquarium & Underwater Restaurant Designer
Civil and Structural Engineers | Aquarium Design Consultants | Coolstore Specialists | Architectural Designers
Aquarium and Underwater restaurant design specialist

Undersea Restaurants


In February 2004 M.J. MURPHY LTD was approached by Crown Company and Hilton Maldives Resort & Spa (previously called Hilton), a very well established property and tour company in the Maldives, to design & supervise construction of a revolutionary new undersea restaurant. It was to go alongside a coral reef on beautiful Rangali Island , where the Hilton Hotel chain was running their highly successful Hilton Maldives Resort & Spa (many awards).  

We proposed the use of our 5m wide acrylic arch, after its successful use on the National Science Centre Aquarium in Kuala Lumpur. Crown Co & Hilton were greatly excited by this idea, and design began in earnest in March 2004.

Initially, the design was based on the assumption that ‘Ithaa’ would be completely built on the beach on Rangali Island, winched down into the water on rails, floated out to the site, and sunk below the water using lots of sand.

This entailed many calculations to check centres of gravity, centres of flotation, stability in the water, and adjustments to size, shape, volume and weight distribution to make it as efficient and stable as possible, - as well as being user friendly and looking stunning. The stairs at one end were particularly challenging because of the complex out-of-balance forces they induced.  

‘Ithaa’ was thankfully located inside the main coral reef, so it was protected from the ravages of the Indian Ocean outside. But our design still had to accommodate all possible load combinations induced by the tidal rise and fall, wave action, different pressures while sinking the unit, and even an allowance for future sea level rise from global warming.

When construction started in May 2004 it was obvious to us all that it was much easier to build ‘Ithaa’ completely in Singapore, and with better quality control.

Hence from July – October 2004, Ithaa's steel structure was fabricated and painted; concrete ballast added, the 5m acrylic arches installed and silicone sealed; air conditioning ducts and electrical ducts added – all in Singapore.

In the meantime on Rangali Island, 4 huge steel pipe piles were vibro-hammered into the seabed, to form the secure base of the unit after it was sunk.

Then on 1 st November 2004, Ithaa was lifted onto a huge ocean-going barge with its own 300 tonne capacity crane on board. Ithaa weighed 175 tonnes at this stage.

It took the barge (with tugboat) 16 days to make the journey to the Maldives. And on the 19 th November 2004 the BIG DAY came… the sinking of Ithaa.

There were people, boats and machinery everywhere! Even a film crew...all arriving to watch the occasion.

Crown Company’s organisational skills were superb, and everything was attended to. The crane-barge lowered Ithaa into the water over the piles. Professional divers were ready, and over the course of the day, 50 keen Maldivian men shifted 85 tonnes of sand ballast (in sandbags) into the belly of Ithaa, to allow it to sink onto the 4 piles below. It was an amazing day.

After Ithaa came to rest on the piles, the divers (the next day) poured concrete into the piles to lock Ithaa down securely to the piles. Our job was done, and very successfully.

All that remained to do, was for Crown Company (under separate contracts) to build the connecting jetty to Ithaa’s stairs, a ‘grass’ entry hut, do the architectural fit out inside the restaurant, and install the air conditioning.

At the same time, Hilton staff were designing new cutlery, and new Maldivian menus, lighting & décor for Ithaa.

Then on Boxing Day 2004, we all got a huge fright when the terrible tsunami stuck the region. Whilst we were not worried about the structural ability of Ithaa to withstand the tsunami, we were much more worried that the wave would top the stair entrance, and fill the restaurant with water.

If it did, then the entire 85 tonnes of dry sand ballast would have had to be removed, causing great uplift problems on the piles…a major structural concern.

However with great relief, we were happy to see the wave reached up to just 300mm below the stair entrance, the sand kept dry, and Ithaa survived her first big natural drama with flying colours!

We believe the tsunami had to pass over many shallow coral reefs before striking Rangali Island, hence considerably reducing its size...thankfully.


In April 2005, Ithaa proudly opened its doors for business. Hilton’s marketing team went into action – emphasising the world-first uniqueness of the restaurant – and the response to date, worldwide, has been amazing. (check out google search for undersea restaurant).Click here to see video clips of the project.

Underwater restaurant by Mike Murphy
Undersea restaurant Maldives


                  On Special Occasions, Ithaa can be converted to a glamorous bedroom.


M.J. MURPHY LTD wish to profoundly thank Crown Company and Hilton Hotels for the opportunity to design this fascinating project, and we wish them and Ithaa great success in the future. The project has featured in the May 2005 issue of the IPENZ magazine (Institute of Professional Engineers of NZ), and in many other magazines around the world and in March 2014 was awarded the amazing title of 'The Most Beautiful Restaurant on Earth" by the Daily Meal.’