A working lighthouse is one of the first visible signs on arrival at Flat Holm
Boat trips to the island six miles off the south Wales coast from Cardiff are up and running for the summer.
Flat Holm, which lies in the Bristol Channel, is a Site of Special Scientific Interest and is home to a wealth of wildlife.
Mankind has also left its mark with a working lighthouse, Victorian cannon and World War Two defences.
Day trips and residential visits can be booked through the Flat Holm Project, which is run by Cardiff Council.
Flat Holm was named a Site of Special Scientific Interest in 1972 in recognition of the gull population that inhabits the island, the special range of maritime grass species which withstand high levels of salt, the geological formation of the island and its inter-tidal zone.
Gulls may be a nuisance in the city but the island is an ideal home
The gull population consists of Herring Gulls which nest on the outer cliff edges, the Lesser Black Back Gull which nest on bare ground and the Greater Black Back Gull.
There are over 8,000 birds on the island - 4,000 pairs of Lesser Black Back Gulls, and approximately 400 pairs of Herring Gulls.
The two halves of the island are managed separately: one half is preserved for the ground nesting birds whose activities enrich the soil and encourage plant growth; the other is kept relatively bird free to preserve the maritime grass species.
10,000 years ago, Flat Holm was a hill in the midst of a wooded valley. Some of the woodland species that would have grown here years before survive today - Bluebells and Slow Worms to name but two.
Slow worms are not worms or snakes but legless lizards
Slow Worms are protected on the island and can be found under rocks and logs - they are commonly mistaken for snakes but are actually legless lizards.
There is a large population of rabbits on the island resulting in many rabbit holes underfoot - the rabbits were introduced in the 12th century and farmed as a source of food.
Seals can sometimes be seen in the sea although they do not breed at Flat Holm.
The island was also home to a tortoise named George although he hasn't been seen for about a year.
Birds and the wind carry many airborne seeds to the island producing a wide collection of meadow plants.
There are many rare examples such as the Wild Leek or allium ampeloprasum - Flat Holm is one of only five places in the UK where it grows.
The island has an interesting and varied human history. Used since the 6th century as a place of religious retreat and rural agriculture, it was heavily fortified in the Victorian Era and in World War II.
In the 1880s one of the island's farm buildings was used as cholera hospital until a small west facing building was built for the purpose. The hospital buildings are now listed, and currently in disrepair awaiting restoration.
In 1897, Marconi and his team made history with the world's ever radio transmission across water from Flat Holm to Lavernock Point.
Many of the buildings on Flat Holm are in need of restoration
The Flat Holm Project arranges scheduled visits to the island between March and October from its base in Cardiff. Booking in advance is essential.
The visit to the island is about 5-and-a-half hours long including the boat ride and three hours on the island - sailing times are dependent on the tides.
The tour around the island takes around two hours. After the guided tour hot drinks are available before boarding the boat back to Cardiff.
Residential visits are also available for groups who want to stay on Flat Holm as well as opportunities for educational and working groups.
For further details contact the Flat Holm Project Office on 029 20 877912 or 029 20 877941 or email firstname.lastname@example.org
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