11 miles off the coast of Kinsale in the Irish sea: A Newtsuit at sea floor examining the Lusitania wreckage.

Tim Carey's photo of divers Richard Wakefield and Steve Phillips on one of his many dives to the Lusitania wreck, where his team brought to the surface

The sinking of the RMS Lusitania created a tidal wave of revulsion around the globe; with sensationalist newspaper headlines such as "the ghastliest crime in history" being commonplace.

Almost from the moment the torpedo sped from U-20, the Lusitania seems to have courted controversy on a grand scale and has always been a ship of intrigue.

Just some of the controversial issues are whether or not the vessel contained priceless works of art in lead containers which were in the care of Sir Hugh Lane, how many torpedoes were fired, whether or not the liner was a legitimate target and theories have also been put forward that the British admiralty steered the ship into the path of U-20 to help bring America into the war.

At 31,550 tons, the Lusitania is a huge shipwreck and is much dilapidated from the sleek elegant vessel which crossed the Atlantic in luxurious style and in record speeds in the early 20th century. Added to this the vessel is often festooned in abandoned snagged fishing nets which could prove lethal to a diver should they become entangled.

Located almost 12 miles from the Old Head of Kinsale, the wreck lies in almost 94 metres of water, meaning that any diver visiting it has to bring mixed gases and will have huge decompression penalties on ascent in order to avoid the bends.

Most people's mental image of diving at these depths comes from television documentaries which are for the most part shot in tropical clear waters and which give a very misleading picture of what it is like to dive to 90 metres in Irish waters. In addition to the tempestuous seas off the Irish coastline, there is also generally a complete lack of ambient light below 65 metres and diving to these depths could be compared to using a torch at night.

For most recreational scuba divers the maximum diving limit is 40 metres with probably less than one per cent of divers having the certification to even contemplate a dive over 90 metres.

For a mere 25 minutes on the bottom, the diver will incur a penalty of almost three hours of decompression stops (to allow the gas bubbles to slowly leave their body) on ascent after the dive.

If anything goes wrong then the dive team needs to be self-sufficient to be able to sort any eventuality underwater; if for any reason the diver was unable to complete the in-water decompression then the dive could well prove fatal. For this reason dive trips to the Lusitania are generally by invitation only. In addition to the diving certification, costs and other barriers, each group also needs a state licence from the heritage service, Dúchas, as well as the permission of the wreck's owner Gregg Bemis.

The other major stumbling block in mounting diving expeditions to the Lusitania is the pernicious nature of the Atlantic Ocean which results in well over half of the planned trips being aborted.

So why do divers make the effort? Well, for wreck divers, descending to the Lusitania is a bit like climbing Everest for climbers. Added to this mix is all the intrigue and controversy surrounding the vessel and the fact that it is regarded as the second most famous shipwreck in the world after the Titanic.

I first dived the wreck in 2004 and over the past decade have been lucky enough to be involved in almost a dozen different expeditions to it, around half of which were cancelled due to Atlantic storms. For those who persevere and make the necessary sacrifices the rewards are immense.

After dropping through a 90-metre water column and accustoming your eyes to the darkness and making all the necessary checks of everyone's diving equipment; the first glimpse of the vessel is a huge feeling of exhilaration. Then you realise you have to make the most of the precious "bottom time".

Swimming around the wreck is a very touching experience and is like transcending time to an era when millions of men suffered horrendous injury and death as the world was embarking on the folly of global conflict.

The most intact part of the ship is the bow area (front of the ship) where the diver will see the huge capstan (which hauled the ships anchors). It was here that a 2008 Irish dive team recovered samples for forensic analysis of the .303 ammunition from a breech in the hull.

The team also located empty shell casings deep in the bow of the vessel - these have yet to be recovered and in time may help explain how the ship sank so quickly.

Ornate portholes litter the wreck having since fallen from the steel that once held them firm, brass deck lamps can often be seen embedded in the silt, as well as ceramic sinks, baths and smaller items such as door handles.

When travelling along the edge of the vessel the sight of so many life boat davits can be very thought-provoking, reminding you that these would have been used to launch the lifeboats in the last moments before the ship sank to the seabed.

You occasionally come across items such as the sole of a shoe which acts as a reminder that the Lusitania is still a grave site for a huge number of people. Ornate brass fittings from seats are also a frequent sight, as well as floor tiles and even cutlery - they all act as grim reminders of the tragedy of the sinking.

Diving the wreck over a ten-year period has shown me one inescapable fact - the wreck is constantly corroding and collapsing further and is suffering a lot of damage from fishing nets. I have seen artefacts on the wreck during one trip that the following season have been completely destroyed by a combination of collapse and fishing net damage.

Hopefully in time all these artefacts can be raised by Irish dive teams, conserved and put on display to allow the general public to see iconic items from one of the most famous shipwrecks in the world; rather than being the preserve of just a handful of divers.

The lusitania: learn more

RECOMMENDED READING

Seven Days to Disaster by Des Hickey & Gus Smith (Collins, London, 1981). Dramatised account by two Irish Independent reporters brings the human side of the tragedy to life.

The Sinking of the Lusitania - Unravelling the Mysteries by Patrick O'Sullivan (Collins Press, Cork, 2014). Compelling account of the sinking and the various theories and cover-ups.

Exploring the Lusitania by Robert D Ballard (Madison Press, Canada 1995). Colourful coffee table treatment by man who led a major diving expedition to the wreck.

Lusitania - an Irish Tragedy by Senan Molony (Mercier Press, Cork, 2004). Details of Irish victims of the sinking as well as those who helped rescue survivors and hunted for bodies.

EXHIBITIONS

Cobh Heritage Museum, Lusitania exhibition.

www.cobhheritage.com

The Lusitania Museum/Old Head Signal Tower Project, Kinsale, Co Cork, www.oldheadofkinsale.com

Mersey Maritime Museum, Albert Dock, Liverpool - exhibition titled 'Lusitania: Life, Loss, Legacy'.

www.liverpool museums.org.uk

Dublin City Gallery The Hugh Lane, Parnell Square North, Dublin. 'Hugh Lane (1875-1915): Dublin's Legacy and Loss' honours his vision and philanthropic support for the visual arts in Ireland.

Opens this Thursday, April 30. www.hughlane.ie.

WEBSITES

The Lusitania Resource,

www.rmslusitania.info.

Includes passenger and crew biographies and much more.

Lusitania Online,

www.lusitania.net

RNLI Courtmacsherry,

www.lusitaniacentenary.com

TELEVISION

Monday May 4, 8pm: Sinking the Lusitania: An American Tragedy, Channel 5. A new 60-minute Smithsonian documentary.

Tuesday May 5, 10pm: Dark Secrets of the Lusitania, National Geographic Channel. A team of scientists test four distinct theories to explain the second explosion on the RMS Lusitania.

Thursday May 7, 10.15pm: Lusitania: 18 Minutes That Changed the World, RTE1. This docudrama follows the last voyage of the Cunard flagship through the stories of individual passengers and crew, as well as the commander of the U-20 who fired the fatal torpedo.

RADIO

Friday May 1, 10.30pm: Seascapes, RTE Radio 1. Archive recordings of witnesses and the restoration of The Old Head of Kinsale Signal Tower

Friday May 8, 10.30pm: Seascapes, RTE Radio 1. Interview with Patrick O'Sullivan, author of The Sinking of the Lusitania - Unravelling the Mysteries.

Irish Independent