History of our wreck haven.
Scapa Flow is a large body of water located in the Orkney Islands off the north of Scotland. This body of water provides a natural harbour to shelter fleets and vessels from what could be the wild weather conditions of the North Sea. Scapa Flow also sits in a strategically important location as it provides easy access across to the United States and Canada by going West, down either side of the UK and Ireland by going south or across to Archangel and Russia by going East. It is for these reasons that the flow has been used for hundreds of years, with the Vikings using it as a base whilst they raided and pillaged the UK, before the British became interested in it during the Napoleonic Wars and the War of Independence with America.
World War One
It was not though until WW1 that the British decided to base the majority of the Royal Navy in Scapa Flow.
Whilst the flow provided the fleet with a great strategic location and sheltered water the make up of the Orkney Islands also provided plenty of entrance points that could potentially have been used by the Germans to attack the fleet. In order to prevent this from happening the Royal Navy requisitioned some merchant vessels in order to sink them and block access through the shallower channels, these ships are known as blockships. At the wider and deeper points such as those used by the ferries today, a system of boom nets were used and would be pulled across to allow the British vessels in and out before being closed again when not in use. As the Germans had very advanced underwater technology they also used a system of hydrophones to listen out for underwater propellers which if heard could be dealt with using some remote controlled mines.
This defence worked perfectly in WW1 with one known attempt by the Germans to enter Scapa Flow, made by a U-boat known as UB116 which was picked up on a hydrophone and sunk by a remote controlled mine.
Under the Armistice agreement at the end of the war the Germans had to surrender most of their fleet, so a total of 74 ships were bought up to Scapa Flow in full working order apart from having their firing pins removed so that the guns could not fire. These ships were kept in Scapa Flow with a skeleton fleet over winter whilst peace talks continued until the 21st of June when Admiral Von Reuter, believing these talks to have failed, ordered the deliberate sinking and scuttling of the fleet in order to prevent them falling into enemy hands. The British managed to prevent some of them from sinking but 52 still went down to the seabed in the biggest loss of shipping ever recorded in a single day! Many of these have now been salvaged either in a huge salvage operation with 7 ships remaining as well as debris sites from some of the others.
World War Two
As the defences had worked perfectly in WW1 no changes were made to the strengthen Scapa Flow in between the two wars, in fact the only change that was made other than the deterioration of the defences over time was that one of the blockships at what is now Churchill Barrier 1 was turned 90 degrees to the side to make it easier for the local fisherman to get in and out of the flow. This weakening of the formally impenetrable Scapa Flow was noted and exploited by the Germans who decided to launch an attack using U-47 under the control of Admiral Gunther Prien. U-47 entered Scapa Flow on the night of the 13th of October 1939 and fired various torpedoes, one of which caused the sinking of a Royal Navy training vessel, HMS Royal Oak, the torpedo caused a huge explosion making the ship sink in less than 8 minutes with the loss of 833 on board. Gunther Prien sails back out of Scapa Flow the way he sailed in and gets all the way back to Germany where he receives a hero's welcome as he has achieved what was formally believed impossible and is awarded the Iron Cross personally by Adolf Hitler.
For the British this showed that the Flow was not as well defended as we believed so they started to enhance defences by sinking more blockships. In order to provide a more permanent defence, Winston Churchill who was the First Lord of the Admiralty came up with the idea of building some barriers between the islands to block the entrances entirely. They bought up some Italian prisoners of war who had been captured during the North African campaign to help build these barriers which were not finished until 1946 but would have blocked the entrances in and out of Scapa Flow since 1941.
Present Day Diving
For us as divers all of these events have lead to one of, if not the, greatest wreck diving site in Europe which makes the perfect playground for technical diving.
The shallow blockships at the Churchill Barriers would used to have been in a vicious current but the barriers mean that they now provide a great sheltered and shallow training site.for those new to technical diving, This is where we carry out our TDI Intro to Tec and PADI Self Reliant courses as well as day 1 one our TDI Advanced Nitrox and Decompression Procedures courses, meaning you will be learning new skills at the same time as diving on some important historical shipwrecks with some great swim-thrus as an added bonus.
The remaining 7 ships from the German High Seas Fleet as well as the various other wrecks in Scapa Flow are a different scale to the wrecks seen at the shore though, immense ships that really have to be dived on to be believed. With Depths ranging from 16 down to 46 meters they sit in the perfect range for both guided technical dives and those wanting to learn how to carry out decompression dives in an extraordinary underwater environment.
For more information on the wrecks of Scapa Flow please follow the link below.