Skip to content

King Charles’ Castle

King Charles' Castle

King Charles’ Castle on the Isles of Scilly

Tucked away in the sub-tropical paradise of Tresco Abbey Gardens lies a quaint little slice of English history. The ruins of King Charles’ Castle on the Isles of Scilly provide a charming diversion amongst lush exotic plants and towering palms for visitors.

Once an impressive garrison during the English Civil War era, kids will love letting their imaginations run wild clambering over what remains of this unique coastal fortress today.

Here’s everything you need to know for visiting this tropical time capsule with a difference

King Charles' Castle

Getting There

To explore the ruins of this atmospheric castle, you’ll first need to hop on over to the beautiful Isles of Scilly!

The quickest way is booking a passenger ferry or flight from mainland Cornwall at Penzance over to St Marys – the largest island.

Small boats then frequently shuttle between St Mary’s Harbour and Tresco Island throughout the day – it’s only a short 10 minute trip.

Once on Tresco, following signs from New Grimsby Quay leads uphill directly to the world-famous Tresco Abbey Gardens after a quick 150 metre stroll. The castle ruins sit nestled on the side of the gardens closest to the coast.

Opening Times & Tickets


Entry to the Castle is free and it is open at any time during the light.

King Charles’ Castle is managed by English Heritage.

Once inside, you’re free to explore the castle ruins at your own pace. No extra tickets or tour guides needed!

It’s easy to combine a castle visit with a full morning or afternoon admiring Tresco’s exotic plants and Valhalla ship figurehead collection nearby too.

english heritage sign at king charles' castle

King Charles’ Castle History

The castle’s origins lie in the turbulent reign of Henry VIII. Tensions with France simmered throughout his rule, culminating in open war in 1538. Henry responded by fortifying the English coastline, constructing new artillery forts to counter the growing threat of French warships armed with the latest cannons.

This legacy of coastal defense fell to his son, the young Edward VI, who ascended the throne in 1547. Facing renewed hostilities with France, Edward’s Lord Protector, Edward Seymour, recognized the strategic importance of the Isles of Scilly. In 1548, construction began on a new fort on Tresco, overlooking the strategic New Grimsby harbor.

A Flawed Design and Shifting Fortunes

Completed in 1551, King Charles’ Castle, named after its namesake who would ascend the throne decades later, was intended to be a formidable guardian. Its design featured a central gun platform surrounded by earthen ramparts, bristling with cannons aimed to repel any hostile incursion.

However, the castle’s design had a fatal flaw. Its guns were positioned too high above the harbour, rendering them ineffective against ships attempting to enter. This oversight, coupled with its isolation from other fortifications, made King Charles’ Castle vulnerable.

Despite its shortcomings, the castle played a role in the English Civil War. In 1651, Royalist forces occupied the Isles of Scilly, using King Charles’ Castle as a base. However, Parliamentarian troops soon arrived, and realizing the castle’s weaknesses, they simply bypassed it, landing on the opposite side of the island.

King Charles I

A Legacy in Stone and Memory

The castle’s military significance waned, and by the 18th century, it stood in ruins. Yet, its weathered ramparts and silent cannons continue to captivate visitors. They offer a glimpse into a bygone era of maritime conflict and remind us of the ever-shifting sands of military strategy.

King Charles’ Castle is not just a pile of stones; it is a testament to human ambition, strategic oversight, and the enduring allure of the Isles of Scilly. Today, it stands as a popular hiking destination, offering breathtaking views of the surrounding coastline and a chance to connect with the island’s rich and often turbulent past.

Click here for an audio tour of King Charles’ Castle by English Heritage.

What to See & Do

The castle ruins sit peacefully these days tucked amidst Tresco’s plunging palm tree valleys and lush flowers. Exploring is free-flow once you’ve entered the gardens – wander at your own pace.

Kids will love scrambling over the walls and foundations that do still exist. Count how many cannons they can find mounted in place!

Top things visitors enjoy are:

  • Reading stories on information panels
  • Admiring perfect seaviews over Bryher and Samson Islands
  • Climbing lookout steps to spot the fort layout
  • Imagining soldiers firing cannons in battle
  • Playing hide and seek around the site!
king charles' castle

Tips for Visiting

  • Visit in the summer when odds of sunny dry weather are higher
  • Pack swimming costumes as it combines well with enjoying the gardens and beaches
  • Have a bucket and spade for fun beach time afterwards!
  • Stop for lunch at the popular garden cafe or New Grimsby Boathouse nearby

Frequently Asked Questions

Are dogs allowed? – Yes, well behaved dogs are welcome

Is it wheelchair accessible? – The walk to get to the castle is along a natrual path with heather and will get muddy in the rain. Not easy for wheelchairs.

Is there a cafe or gift shop? – No facilities at the Castle.

castle sign tresco

Nearby Attractions

Think about visiting some of these places too:

  • Tresco Abbey Gardens – Take a short boat trip to car-free Tresco and explore the breathtaking subtropical Abbey Gardens, home to exotic plants from 80 countries that rarely flower in the UK climate.
  • Isles of Scilly Museum – Found in St Mary’s Hugh Town, this museum explores the islands’ history and culture through local artefacts, art, pilot gig boats, plus archaeology and environmental displays.
  • Cromwell’s Castle – A short stroll from King Charles’ Castle on Tresco, this ruined artillery fortress from the English Civil War offers beautiful views over Scilly’s islands from the remains of circular gun platforms.
  • Bryher Island – Hop across to peaceful Bryher, Scilly’s smallest inhabited island, for scenic coastal walks spotting wildlife and shipwrecks. Stop for homemade cake at the Fraggle Rock cafe.
  • St Mary’s Boat Trips – Join a relaxing wildlife spotting or inter-island hopping boat trip to uninhabited islands like Teän or the Western Rocks to observe seabirds and grey seals.
  • Porthcressa Beach – Catch a boat back to St Mary’s and enjoy the brilliant white sand and tropical blue waters of Porthcressa – one of Scilly’s most stunning beaches.
  • Hugh Town – Wander the tiny picturesque capital of Scilly with its old-style cottages, local shops, galleries and cafés plus the quay lined with colourful fishing boats bringing in the daily catch.
  • Star Castle Hotel – This atmospheric Elizabethan stone fort turned hotel on St Mary’s offers history and paranormal tours plus wonderful dining views over the islands.
  • St Agnes Lighthouse – Visit Britain’s most southwesterly working lighthouse on scenic St Agnes, then spot seals and seabirds on coastal walks to Cove Vean and other beaches.

Immersed within the spectacular Tresco Abbey Gardens yet often missed by visitors rushing past lies the unique ruins of atmospheric King Charles’ Castle. Kids will revel in this secret hideaway as imaginations are let loose! And when they just can’t scramble another foot, simply relax amongst swaying palms until it’s time to depart this tropical Scilly haven once more.

Leave a Reply

Your email address will not be published. Required fields are marked *