A guided tour in words, maps and photos to exploring Tresco, the Abbey Garden and Scilly's Holy Isles of Teän and St Helen’s. People travel to Tresco from all over the world to visit the Abbey Garden, which is a northern sanctuary for plants normally found in the southern hemisphere and subtropics. The gardens are laid out around the ruins of a small 12th century priory church. However, the origins of a religious foundation on Tresco go back much further to the 6th or 7th centuries AD, when Celtic holy men and women arrived on Scilly from Ireland and Wales. The tradition of seclusion and solitude was then carried on, in a different form, by the lighthouse keepers who lived on Round Island. The sea immediately around Round Island is deep and turbulent and, despite being so close to the other islands, the keepers could find themselves marooned for days beyond the end of their watch by stormy seas.