In the Summer months of May, June and July the days are long on the islands, with up to 20 hours of daylight. Unlike much of the Highlands, the soil on Orkney is fertile and the sea bountiful, and for these reasons, humans have been coming to these islands to farm and fish for millennia, and as archaeologists are just beginning to discover, Mainland Orkney was a place of pilgrimage to the pre-historic tribes of the British Isles, perhaps even the epicentre of neolithic life here! The amazing history of Orkney does not begin and end with the stone age, the islands were also very strategically important during WW1 and WW2 and evidence of this can be seen everywhere; from scuttled ships and machine gun posts to the Churchill Barriers - the causeways that connect Mainland to the Holm Islands, Burray and South Ronaldsay, as well as the incredible Italian prisoner of war chapel on Lamb Holm. Scapa Flow, with its sheltered anchorage, became one of the Royal Navy's largest wartime bases in the Twentieth Century and was pivotal in the movement of supplies and weapons for the Arctic and Russian convoys. As a result of this activity Scapa Flow was frequently targeted by German U-boats and consequently there are many wrecks on the sea bed around Orkney. This fact, coupled with the clear waters of the North Atlantic make the area a haven for divers. The Vikings also played a huge part in the history of Orkney, ruling over the Northern Isles between the 9th and 15th centuries. Their legacy can still be clearly felt through place names, such as Stromness, Orphir and Birsay and most obviously through the beautiful towering red sandstone edifice of St Magnus Cathedral which dominates the islands' capital Kirkwall.