Qualla: Cromwell's Castle

Cromwell's Castle: Introduction

Sat, 23 May 2026 00:00:00 GMT

Photo credit William Borlase (1695 – 1772), Public domain. When Admiral Robert Blake's Parliamentary forces captured Tresco in June 1651, the Royalist garrison of King Charles's Castle blew up their own fort and fled. The stone they left behind did not stay where they dropped it. The following year Blake's masons hauled it down the hillside and built a new fort on the rocks at the water's edge - a three-storey round tower with walls almost thirteen feet thick. They called it Cromwell's Castle, after the Parliamentary leader, and unlike the failed castle uphill its guns could actually fire at ships entering New Grimsby harbour. English Heritage now describes it as 'one of only a few stone fortifications that survive from the Interregnum' - the brief eleven years between 1649 and 1660 when England was a republic. The interior wooden floors are gone, but the spiral staircase still climbs to a vaulted stone roof, and the six gun-ports on the parapet still look out across the channel to Bryher.

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Image: William Borlase (1695 – 1772) | Public domain

Cromwell's Castle: The Stone from King Charles's Castle

Sat, 23 May 2026 00:00:00 GMT

Photo credit Andrew Abbott, CC BY-SA 2.0. The site already had a small sixteenth-century blockhouse on it - a low fortification at the water's edge beneath the failed King Charles's Castle uphill. Between 1651 and 1652 Sir Robert Blake had a three-storey circular tower built on top of this blockhouse, 13.45 metres across...

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Image: Andrew Abbott | CC BY-SA 2.0

Cromwell's Castle: The Dutch Threat

Sat, 23 May 2026 00:00:00 GMT

Photo credit Richard Knights, CC BY-SA 2.0. Why build a new fort at all? The Parliamentary forces who took the Scillies in 1651 were not primarily worried about a Royalist counter-attack. They were worried about the Dutch. England and the Netherlands were drifting toward what would become the First Anglo-Dutch War of 1652-...

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Image: Richard Knights | CC BY-SA 2.0

Cromwell's Castle: Abraham Tovey's Gun Platform

Sat, 23 May 2026 00:00:00 GMT

Photo credit Daniel Bagshaw, CC BY-SA 2.5. After the Restoration of Charles II in 1660 the castle was surveyed and patched up. By the 1730s it had ten artillery positions on paper but not nearly enough working guns to fill them. Then in 1739 the War of Jenkins' Ear broke out between Britain and Spain - a conflict named af...

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Image: Daniel Bagshaw | CC BY-SA 2.5

Cromwell's Castle: The Surviving Interior

Sat, 23 May 2026 00:00:00 GMT

Photo credit Stewart Horn, CC BY-SA 2.0. By 1922 the lease had passed to Arthur Dorrien-Smith, the Tresco landowner, who handed several Tresco properties - including the castle - into the guardianship of the Ministry of Works. English Heritage took over in due course, and today Cromwell's Castle is open to visitors. The...

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Image: Stewart Horn | CC BY-SA 2.0