The most iconic superyachts do not always spring from a blank drawing board. Instead, many have emerged from an owner's vision to transform or give a second life to vessels with storied pasts. From fishing trawlers to retired naval frigates and cruise liners, BOAT looks into the world's largest conversions...
Read More/Beauty and the beast: What are the pros and cons of commercial and military conversions?1. Yas | 141m
Yas was first delivered in 1978 as a naval frigate named HNLMS Piet Hein. After two decades of service in the Dutch Royal Navy and a decade serving the UAE military, she was released from duty and converted into a private yacht under the codename Swift 141. Jacques Pierrejean is the man behind her futuristic design, which includes a giant glass dome. The entire project was carried out in Abu Dhabi and the vessel was extended by 12 metres to accommodate a new pool deck. In 2011, she was relaunched in Port Zayed in Abu Dhabi and is the 11th largest yacht in the world.
2. OK | 146m
Formerly christened Super Servant 3, this semi-submersible expedition yacht began life in 1982 in the hands of a Japanese commercial shipbuilder. Now named OK, after a three-year conversion project at Karmarine shipyard, with Timur Bozca at the helm of the redesign to create a "floating island concept that could hold many toys." The design brief came to life, with 3,000-square-metres of deck space that can house a 46-metre sailing yacht or convert to an open-air tennis court. Other impressive highlights include a swimming pool, a botanical garden and four aquariums.
3. Maryah | 125m
This 125-metre former Russian research vessel has sailed under the names Dalmorgeologiya, Fortune and Czar, before she was converted into a SOLAS-compliant superyacht by Greek shipyard Elefsis in 2015. Details of her interiors have been closely guarded but are said to feature a cinema and accommodation for 54 guests across six decks.
4. Alexander | 121.95m
Alexander first hit the water in 1965 and served as a cruise liner – Regina Maris – until 1985 when, after several changes of ownership, she was converted into a superyacht by Greek shipping tycoon John Latsis and owned by the family until 2015. She was extensively refitted in 1985 and then again in 1998, with accommodation for up to 80 guests in 40 staterooms. Highlights include a swimming pool, hospital, gymnasium, a 27-seat cinema and a helicopter landing pad. Previous guests on board the iconic yacht include King Charles III, President George Bush Senior and King Constantine of Greece. Speculation points to the current owner being a member of the Saudi Arabian royal family.
5. Project Y910 | 120m
Built in Poland in 1990, the 90-metre vessel served as an offshore supply ship named after the Russian writer Vladimir Chivilikhin. The ship was in service until 1998 when her owner decided to convert the vessel into a charter yacht under the project name KAY. Work on the hull began at Keppel Singmarine before the yacht made her way to Italy for outfitting at Fincantieri. The half-built project was put up for auction in November 2021. Currently lying at the Fincantieri shipyard in Trieste, she patiently awaits a new owner.
6. Dream | 106.5m
The 106.5-metre Dream was born into the world as a humble passenger vessel before she embarked on a near decade-long conversion project to fulfil the lifelong dream of an ambitious new owner. Under the project name Poseidonos, work began in 2008 at Chalkis Shipyards in Greece with exterior design by Studio Vafiadis and an all-new interior by Ciarmoli Queda Studio. The team's efforts were rewarded when Dream picked up a Neptune for Best Converted Yacht at the 2019 World Superyacht Awards. Highlights include a swimming pool, cinema room, dive centre, conference room and helipad. As per the owner's request of desiring a "fresh sea breeze", there are 66 opening portholes, 20 manually opening windows and 112 electrically opening windows throughout the yacht.
Read More/Dream: Inside the Breathtaking Conversion of the 106.5 Metre Superyacht7. Christina O | 99.15m
Christina O was built for the Canadian Navy as an anti-submarine frigate under the name HMCS Stormont. Following World War II, she was purchased for scrap value by Greek shipping magnate Aristotle Onassis. A six-year conversion ensued and she was reborn in 1954 as the private yacht Christina O, which was regularly seen to host royalty and the Hollywood A-list – including Greta Garbo, Marilyn Monroe, Frank Sinatra, Sir Winston Churchill, Grace Kelly, John F. Kennedy and Elizabeth Taylor.
Read More/The real story behind the Triangle of Sadness superyacht8. Voyager | 91.4m
Previously known as Danah Voyager, the conversion of this former offshore supply ship is the largest to take place on American soil. First delivered by Swiftships in 1997, the 63-metre commercial vessel arrived in Dania Cut in Florida in 2016 and emerged from the sheds three years later as a 91.4-metre explorer. An extra 30 metres translated into accommodation for 70 crew and a dive centre with a decompression chamber to support deep dives – one of the main purposes of the yacht.
9. Dubawi | 90.6m
Dubawi began life in 1989 as a small passenger ship built by Cantieri Navale Ferrari before she was converted into a private yacht two decades after her launch. The project was awarded to Dubai shipyard Platinum Yachts and remains one of its biggest projects to date, second only to the 162-metre Dubai. Work included a five-metre extension, a restructuring of the top deck and an entirely new interior.
10. Gaia Blu | 82.9m
Initially built by Orenstein & Koppell in Germany in 1981 as a fisheries protection vessel, Gaia Blu underwent an extensive three-year refit to become the world’s first year-round philanthropic research vessel conducting marine research. She has been instrumental in significant discoveries, such as identifying 500-metre-tall coral reef in the Great Barrier Reef, Australia. In 2022, the owners of the Schmidt Ocean Institute donated the vessel, then named Falkor, to the Italian National Research Council. The Council is now offering scientists and researchers the opportunity to come on board, with proposals being accepted for projects to be conducted in the Mediterranean between March and December 2025.
11. Arctic P | 87.6m
Arctic P started life in 1969 at the Schichai-Unterweser shipyard, where she was built as the "strongest, toughest, salvage rescue vessel". She was relaunched in 1993 as a converted explorer and extensively rebuilt in 2020 at Palumbo's facility in Malta, where Arctic P became a charter yacht that still preserved her legendary toughness. As well as racking up vast global nautical miles, she also holds a Guinness World Record for travelling 677 nautical miles from the South Pole. Today she is a perfect charter yacht, brimming with amenities and a toy box ready for adventurous guests. Accommodation is across 12 guests and 28 crew.
12. Bleu De Nimes | 72.3m
Blue de Nimes has undergone not one, but two major rebuilds throughout her life. She began life as Lodestone, a 55-metre British Navy ship, before being purchased at auction by a buyer looking to convert the vessel. Finding no suitable shipyard to complete the project, the owner established his own. Keeping the meticulously maintained hull intact, the first rebuild in 2005 transformed the superstructure, resulting in nine cabins. In 2016, the second rebuild extended the yacht by 16 metres and increased the volume by 600GT, converting her into a well-appointed charter yacht. Aligning with the Passenger Yacht Code (PYC), she can now legally charter with 28 guests.
13. Serenity | 72m
Built by the Australian yard Austal in 2003, Serenity was delivered as a mini cruise ship and later transformed into a private superyacht in 2017 under the design prowess of Luiz de Basto. The yacht features a swimming pool, cinema room, expansive deck spaces and various entertaining areas. She accommodates 30 guests in 15 cabins, maintaining a one-to-one guest-to-crew ratio with 31 crew members.
14. Ocean Falcon | 66m
A 66-metre former offshore rescue vessel, dubbed Ocean Falcon, arrived at Lürssen in 2022 with the ambitious intention to convert her into an expedition charter yacht. Original plans included a submarine, a 10-metre swimming pool, helicopter facilities, and a diving centre, though the project was dropped by both Icon Yachts and Lürssen. Ocean Falcon's future remains uncertain, though she is now docked in Rotterdam, the Netherlands and seeking a new owner with Northrop & Johnson. Things are looking up, as the brokerage has confirmed several bids from "leading shipyards" are already in place.
15. Te Streep | 49.5m
Built for the Belgian government as a hydrographic survey vessel, Te Streep was purchased by her current owner in 2021 and has been recently modernised in a 2023/24 refit period with upgraded navigation and a refreshed interior. The yacht is for sale and as a fully functional, all-steel explorer yacht, offers a rare opportunity to add to her conversion story. Her rugged exterior features a graffiti project by urban artists from Belgium, a touch-and-go helipad, and space for submersibles, tenders, and toys, making her poised for the next adventurous chapter.
16. Scintilla Maris | 46m
Translating to "spark of the sea", Scintilla Maris was converted from a 1988 Dutch fishing trawler. Built by Maaskant (now part of the Damen Group), the vessel underwent a comprehensive four-year rebuild from 2019 to 2024. Scintilla Maris underwent a few key alterations to help reduce the tonnage from 570GT to below the 500GT threshold, while Vripack was called upon to reimagine her interiors. She was also equipped with hybrid-electric propulsion. Today, she is a full custom expedition yacht for charter with Burgess, with space for ten guests.