One of the world's largest explorer yachts,_ Nomad_ started life as Aussie Rules and was originally owned by professional golfer Greg Norman. In 2004, she was sold to Florida businessman Wayne Huizenga, who extended the bridge deck to carry a helicopter.

In 2008 she had a lengthy refit and was renamed Nomad. She has an ultra-modern stabilisation system that provides comfortable cruising in most conditions.

Other notable features include an observation lounge and cinema on the upper deck and a huge alfresco dining area on the main deck aft.

Builder / naval architecture:Oceanfast
Interior design:Sam Sorgiovanni
Former names:Aussie Rules, Floridian

Olivia was built as a hydrographical survey vessel for the Russian Navy. She was then converted into an explorer yacht in 2010 by OY Laivateollisuus and Rouvia Road Yacht Design & Construction.

The conversion means that Olivia now has all the toys and technology needed to rival the modern superyacht, including the latest navigational equipment, stabilisers, Jet Skis and a 12-person superyacht spa pool.

She is driven by a single screw Deutz diesel engine, and has an impressive range of more than 9,000 nautical miles.

Olivia's ice classed hull means she is a true explorer. She is even certified by the Royal Institution of Naval Architects.

Builder / naval architecture:OY Laivateollisuus
Exterior styling / interior design:Rouvia Road Yacht Design & Construction
Former names:Delta Bravo One

The iconic yacht Skat was built for the man behind Microsoft Excel — Charles Simonyi. As with many of the world's largest explorer yachts, Skat has the appearance of a naval vessel, with its grey paint scheme and angular features.

Simonyi asked for the angular look, as steel and aluminium come in flat plates. "Why spend time and tonnes of filler to make it look like something its not?" he asked.

The explorer yacht is uncluttered and the interior makes use of only a few specified materials. Wide corridors and side decks, and large practical stairwells make Skat a functional vessel, and set her apart from other yachts. The guests cabins are all on the main deck, leaving the lower deck entirely for crew use and storage.

Builder / naval architecture:Lürssen
Exterior styling:Espen Øino
Interior design: Marco Zanini

Enigma XK _was built in 1988 as _Norna, a tough Scottish Fisheries Protection Agency patrol vessel. During her government service she patrolled the freezing waters of the North Atlantic for illegal fishing.

She was taken out of service in 2010 and has been converted by the Atlantic Refit Centre into an explorer yacht. The vessel was in good condition and so designer Philippe Briand chose to keep most of the original boat, including the original funnel.

Enigma XK has a range of 12,000 nautical miles and completed a season in Antarctica in 2015.

Builder:Richards (1988) / Atlantic Refit Center (2014)
Naval architecture: McFarlane Ship Design
Exterior Design:Philippe Briand
Interior Styling: Veerle Battiau/Vitruvius

Named after a notorious wave off the coast of Fiji, Cloudbreak was built for an owner with a passion for heli-skiing and global exploration. German yard Abeking & Rasmussen delivered this explorer yacht in 2016, having worked with designer Espen Øino to create her steel hull and aluminium superstructure. Her warm and inviting interiors by Christian Liaigre feature a superyacht gym, sauna and massage area. Measuring in at 72.5 metres LOA, she is 16th in our list of the world's largest explorer yachts.

Builder / Naval Architecture: Abeking & Rasmussen
Exterior Design: Espen Øino
Interior Styling: Christian Liaigre

Picchiotti’s flagship, Grace E, is based on her Vitruvius series predecessors: 50m Exuma and 55m Galileo G. The yacht is a collaboration between Vitruvius Ltd, Philippe Briand and the Perini Navi Group.

Grace E is built in aluminium and features a special BOS Hull (Briand Optimized Stretched Hull). The explorer yacht differs from the first two yachts in the series due to her advanced diesel-electric propulsion system. With her two azipods she can cruise at 12 knots for over 7,500 nautical miles.

Grace E also features a range of innovations designed to help reduce her footprint on the areas that she visits, including systems to deal with exhaust fumes and for dealing with garbage management and storage.

“Our intention was to be able to go to any area in the world and retain everything on board in the event of a lack of (disposal) facilities ashore,” said captain Eddie Cooney.

Builder:Picchiotti
Naval architecture & Exterior styling: Philippe Briand / Vitruvius
Interior design:Rémi Tessier

The 73.61 metre steel expedition-capable superyacht Naia (ex-Pegaso) was launched in 2011 by Freire. As well as being one of the world's largest explorer yachts, she is the largest superyacht ever to be built in Spain and underwent a three month refit in 2014 for her new owner.

Naia has many of the attributes of a high-spec explorer yacht, including an HCA certified helipad — the sort normally found on North Sea oil platforms. The black water treatment system is so thorough that the yacht compiles with the strictest regulations, meaning she can travel to Alaska, and four satellite domes provide continuous internet connectivity.

Builder:Freire
Naval Architecture:BMT Nigel Gee & Associates
Exterior Styling:H2 Yacht Design
Interior design:Mark Berryman

Northern Star, originally known as Project Scout, _was delivered to her owner by Lürssen in 2009. Having owned a previous smaller explorer yacht with the same name (now _Polar Star), the owner knew what he wanted when he ordered a larger version.

Similar in style to his previous yacht, Northern Star features an ice-class hull and is robustly designed for permanent use in the northern hemisphere. With a range of 6,000 nautical miles, she combines the luxury of a superyacht with the go-anywhere capability of an explorer yacht.

Northern Star also carries two sturdy Zodiac Hurricane Adventure RIBs as well as a stylish Hinckley tender.

Builder / naval architecture:Lürssen
Exterior styling:Espen Øino
Interior design:Pauline Nunns

Yersin is a steel-hull, ice-classed explorer yacht built at Piriou commercial yard in Brittany. Piriou collaborated with exterior designer Pierre-Jacques Kubis to design a motor yacht capable of cruising the most extreme conditions.

Built for oceangoing navigation, transoceanic passages and ice exploration, Yersin is to be used for research. She carries several tenders to aid the campaigns.

She has a huge range of 12,000 nautical miles and can go for 50 days without needing to take on supplies, meaning she doesn’t need to make landfall very often — a key requirement to make it onto our list of the world's largest explorer yachts.

Builder / **Naval architecture:** Piriou
Exterior Designer: Pierre-Jacques Kubis

Legend (ex-Giant I) was built in Holland as a Class 1 icebreaker for the Soviet Union merchant marine. She served the Russians for 26 years as an oceangoing salvage tug and electronic eavesdropping vessel. After breaking down in an American port she was abandoned and sold at auction by the American authorities. She was bought by René Herzog and converted into a charter yacht.

She recently completed a 12-month refit at Icon Yachts, which included a 3.6 metre aft deck extension to equip the yacht with a swim platform and swimming pool. The helipad is commercially certified and a submarine can be stored in a forward garage. The bulwark and deckhouse were also extended to give her sleeker looks.

The yard has said Legend will be used for adventurous charters in remote areas of the world, including Antarctica, Greenland and the North Pole.

Builder: IHC Holland (1974) / Giant (2003) / Icon Yachts (2016)
Naval architecture: IHC Holland
Exterior styling (2014):Diana Yacht Design
Interior design (2003):John Misiag

In 1994 the Malta Drydock Company converted this oceangoing, ice-classed tug into a luxury yacht for French entrepreneur Jackie Setton. Having changed hands several times she was then sold at auction in 2013 and renamed Sea Ranger.

She has been dubbed as the ultimate expedition yacht. She has a basketball court on her decks along with a swimming pool and helicopter pad, plus the ability to carry a 40 foot cabin cruiser and numerous other small boats on her deck.

She has a staggering range of 31,000 nautical miles she has already cruised the world several times, including visits to the Arctic and Antarctic.

Builder:Schichau-Unterweser (1973) / Malta Drydock Company (1994)
Naval architecture:Kusch Yachts
Exterior styling: Lothar Schimpf
Former names:Simson S,Lone Ranger

Bart Roberts was built in 1963 as Narwhal and used by the Canadian Coastguard. She was sold in 2002 to Floridian businessman Arnie Gemino. His company Tradepower International converted her into a charter yacht named after notorious pirate Bart Roberts.

The ice class vessel saw a huge transformation, with a large amount of work required to turn a pile of metal into a pirate themed luxury yacht. Ownership has since passed on and the former charter yacht and her assortment of toys are strictly for private use.

Builder:Canadian Vickers (1963) / Tradepower International (2002)
Naval architecture:Lennart Edstrom (refit)
Interior design: Tradepower International / K Bamford (refit)
Former names:Narwhal

The 85 metre Pacific, formerly known as Project Josi, was launched in 2010 by Lürssen. The unusual exterior was designed by Argentinean naval architect German Frers, who is renowned for designing some of the world's largest sailing yachts. The interior of Pacific was created by Bannenberg & Rowell Design.

Pacific can accommodate two helicopters and has been spotted travelling all over the world. Previous destinations are believed to include: Australia, Indonesia, Hawai, Costa Rica, the Caribbean and the Mediterranean.

Builder / naval architecture: Lürssen
Exterior styling:German Frers
Interior design:Bannenberg & Rowell

Arctic P was built as an ice-classed, oceangoing tug in 1969 for the Bugsier Towing & Salvage Company. Her pre-conversion career included the rescue of a commercial expedition vessel that ran aground in the Antarctic in 1972.

In 1995 she was converted into a yacht for the late Kerry Packer, formerly Australia’s richest man. The project was managed by the late Claus Kusch, who also converted the smaller tug Simson S (now Sea Ranger, number 10 on this list). The yacht is still owned by the Packer family and can be seen roaming the worlds oceans.

In 2013 Arctic P journeyed from the Falkland Islands to the Antarctic Peninsula, travelling further south than a private vessel had gone in years. After that trip they decided to go further, and in doing so set the record for the furthermost southern latitude of any private vessel on the Antarctic Peninsula in recent years.

The journey took some planning but she is well equipped for the conditions. She has 50mm steel plating on the bow and 30mm on the ice line and as the captain says "we know what she is capable of; she has proven herself a true expedition yacht. She can go anywhere the owner desires".

Builder:Schichau-Unterweser (1969) / Malta Drydock Company (1995)
Naval architecture:Kusch Yachts
Exterior styling: Lothar Schimpf
Interior design:Pauline Nunns
Former names:Arctic

Ice was sold to Suleiman Kerimov following delivery and she is extremely quiet and free from vibration. She features two Azipod units powered by up to eight Deutz generating sets that also provide household power. This makes her environmentally friendly without sacrificing performance, as she is still capable of reaching 18.67 knots.

One of the world's largest explorer yachts, Ice has an arsenal of toys and sailing dinghies as well as a helipad for the Eurocopter EC135 helicopter. A range of 6,000 nautical miles means she can travel anywhere in the world.

Builder / naval architecture:Lürssen
Exterior styling:Tim Heywood
Interior design:Terence Disdale
Former names:Air

Equanimity is built to Passenger Yacht Code meaning she can carry up to 26 guests. The word equanimity means having 'a mental calmness, even in a difficult situation.' For a yacht designed to explore the world's oceans this could be a good mantra.

The steel hulled yacht has been kept much under wraps but does have a 271,000-litre fuel capacity, giving her owner almost unlimited options for exploration. She also features a fully-certified heli-deck, a must have on any exploration superyacht.

Builder:Oceanco
Naval Architecture: Azure N.A. / Oceanco
Exterior styling: Oceanco
Interior design:Andrew Winch Designs

Ulysses is the product of collaboration between two Norwegian companies known for building offshore, commercial vessels. Commissioned by New Zealand businessman Graeme Hart, this explorer yacht is ready for any conditions.

Specially designed to have a long-range, Ulysses is capable of carrying 30 guests to the furthest corners of the world’s oceans. A helicopter pad and hangar as well as a custom 21 metre tender allows guests to explore the most out of reach places.

Currently offered for sale, Ulysses was recently spotted attending the Cannes Yachting Festival.

Builder:Kleven
Naval Architecture / **Exterior Styling:** Marin Teknikk
Interior Design:H2 Yacht Design

Le Grand Bleu was built for John McCaw and subsequently sold to the Russian businessman Roman Abramovich who had her refitted. The main addition was the 16ft swim platform. Le Grand Bleu is now reportedly owned by Ambramovich's friend and business associate Eugene Shvidler.

The yacht has many features that make her ideal for exploration. The large tender garage has storage for two sports boats as well as a landing craft capable of carrying a 4x4 Land Rover for excursions ashore. She even has a 22 metre sailing yacht and a 21 metre Sunseeker motor yacht stored on the aft deck.

Builder:Bremer Vulkan
Naval architecture / exterior styling:Kusch Yachts
Interior design: Di Pilla

Luna is the world's second largest explorer yacht and was built for Roman Abramovich as an upgraded replacement for his former exploration yacht Le Grand Bleu (number 3 in this list).

The yacht was sold to Roman Abramovich's close friend, Farkhad Akhmedov in April 2014. The new owner sent her to the yard in Germany for an extensive refit with delivery due for 2016.

Luna is ice-classed and built to the highest possible standards, allowing her to travel to the far reaches of the worlds oceans. Details of the refit have been kept secret but she is likely to keep her two helipads and large tender garages in the stern.

Builder: *Lloyd Werft / Stahlbau Nord
*Naval architecture: Blue Ocean Yacht Management
Exterior styling:Newcruise - Yacht Projects & Design
Interior design:Donald Starkey

Octopus is the largest explorer yacht in the world and the most recently built yacht of Paul Allen, one of the founders of Microsoft.

Octopus has the capacity for two helicopters at the same time, with landing pads on the aft deck and foredeck. The helipad on the aft deck also has a hangar to store the helicopter away in big seas.

She also has an internal dock, which is perfect for storing the toys that every explorer yacht should have. When the dock is filled with water a 20 metre submarine and a tender of similar size are able to float in and out of their chocks. Once they are secure the water is pumped out before the yacht gets underway.

Paul Allen and the crew of Octopus have been using the yacht as part of an eight year search for a sunken ship. In 2015 they finally discovered the long-lost wreck of Japanese ship Musashi, which sunk during the Second World War.

Builder / naval architecture:Lürssen
Exterior styling:Espen Øino
Interior design:Jonathan Quinn Barnett/Sam Sorgiovanni