Best castles around St Mary's are located on an island in the Atlantic, offering a rich historical landscape. This region features numerous historical sites and fortifications, many overlooking the water. Visitors can explore ancient structures and enjoy walks across the island, experiencing its unique blend of history and natural beauty. The area provides a glimpse into past eras through its well-preserved historical monuments.
Last updated: May 3, 2026
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There is a hotel in the Star Castle. But you can climb the ring of walls and admire the view.
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Ruins of a Royalist Civil War fort which was blown up before it was stormed by Parliamentary troops. A great vantage point over New Grimbsby Sound.
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Small Civil War-era fort blown up by the Royalists before the storming. Fantastic views over New Grimsby Sound.
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Old Civil War fortifications. Before it was conquered by the Parliamentary troops, it was blown up by the Royalists. Wonderful vantage point
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The newer of the two major fortifications was built in 1651 by Parliamentary troops after taking the island from the Royalists. With his well-fortified cannons on the top of the tower, he dominated the entrance to New Grimsby Sound. The tower is freely accessible and has a beautiful vaulted room inside. There is a beautiful view from the upper platform.
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Beautiful castle overlooking the water. In general, it's nice to walk across the island, the sailing boats in the bays, the lively ferry traffic, the harbor lies like a beehive, the awareness of being here in the middle of the Atlantic. A dream.
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Beautiful walk around the Garrison walls. Lots of historic sights to take in.
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St Mary's, part of the Isles of Scilly, offers a rich array of historical fortifications. You can explore ancient structures like the prehistoric Innisidgen Burial Chamber, which dates back to the Iron or Bronze Age. There are also later military structures such as Star Castle, an old fort with a colorful history, and Cromwell's Castle, built in 1651. Additionally, you can visit the ruins of Harry's Walls, a mid-16th-century fortress, and King Charles's Castle, a Civil War-era fort.
Yes, Harry's Walls is noted as a family-friendly historical site. These are the ruins of a 16th-century fortress and are free to visit, offering an accessible historical experience for all ages.
Yes, Cromwell's Castle is freely accessible, allowing visitors to explore its interior vaulted room and enjoy the view from its upper platform. While Star Castle is an old fort, it now functions as a hotel, so access to its historical elements may vary.
Many of the historical sites on St Mary's offer excellent viewpoints. From Cromwell's Castle, you can enjoy a beautiful view from its upper platform. Star Castle overlooks the water, providing scenic vistas. Similarly, King Charles's Castle offers a fantastic vantage point over New Grimsby Sound.
Absolutely! St Mary's offers numerous hiking opportunities that often incorporate historical sites. You can find easy hikes like the Garrison Walls Trail or the St Mary's Prehistoric loop via Bant's Carn & Innisidgen Burial Chamber. For more options, explore the easy hikes around St Mary's or more general hiking routes around St Mary's.
Beyond exploring the castles themselves, St Mary's provides a variety of outdoor activities. You can enjoy hiking trails that pass by these historical sites, such as the Garrison Walls Trail near Star Castle. Cycling is also popular, with routes like the St Mary's loop. For more details on routes, check out the hiking and cycling guides for St Mary's.
The fortifications on St Mary's reflect various periods of history. The Innisidgen Burial Chamber is a significant prehistoric ritual site. Later structures like Star Castle and Cromwell's Castle played roles in military defense, particularly during the English Civil War, with Cromwell's Castle being built by Parliamentary troops in 1651. King Charles's Castle is another example of Civil War-era fortifications.
Yes, both Cromwell's Castle and Harry's Walls are freely accessible to visitors. Cromwell's Castle allows you to explore its interior, while Harry's Walls are the ruins of a former fortress.
Visitors frequently highlight the rich history and the stunning views. Many appreciate the opportunity to walk around the Garrison walls, taking in the historic sights and the beautiful scenery overlooking the water, especially around Star Castle. The ancient history of sites like the Innisidgen Burial Chamber also captivates visitors.
Yes, many of the castles and historical sites on St Mary's are located along scenic coastal paths. For instance, Star Castle is part of a beautiful walk around the Garrison walls, offering views of the sea and lively ferry traffic. Exploring these sites often naturally integrates with coastal walks.
The castles and historical sites on St Mary's span several significant periods. The Innisidgen Burial Chamber represents the prehistoric Iron or Bronze Age. Later fortifications like Harry's Walls date back to the mid-16th century, while Star Castle, Cromwell's Castle, and King Charles's Castle are prominent examples from the 17th century, particularly related to the English Civil War.


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