Levant Mine and Beam Engine is a National Trust property at Trewellard, Pendeen, near St Just. Its main attraction is that it has the world's only Cornish beam engine still operated by steam on its original site. There is also a visitor centre, a short underground tour, and the South West Coast Path leads to Botallack Mine, via a cliff-top footpath.
The property is on the site of the former Levant Mine, established in 1820 and closed in 1930, where tin and copper ores were raised. The mine reached a depth of about 600 metres. It got the nickname 'mine under the sea', because tunnels were driven up to 2.5 km from the cliffs under the sea. The surviving beam engine was built c. 1840 by Harvey's of Hayle.
In 1919 the engine used to transport men between the different levels of the mine failed, leading to the deaths of thirty-one men.
Since 2006, the area has been part of the UNESCO World Heritage Site, Cornwall and West Devon Mining Landscape.
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The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.