Quick answer: two things decide your visit and most guides mention neither. The Mount is closed every Saturday, all year, so the islanders get a day off. And the castle and gardens close for the whole winter — for the 2026/27 season they shut on 1 November and the castle reopens on 21 March 2027. That is not a reason to skip it: in winter the harbour, village, shops and café are free to visit, no ticket, and you walk out across the causeway at low tide. The thing to check is the tide, because the causeway is only open about four hours a day and the times move daily.
St Michael’s Mount is the most photographed thing in Cornwall and the most likely to be got wrong, because what you can do there changes completely with the season, the tide and the day of the week. This is the practical version: when it is open, what it costs, how the causeway works, and what is actually worth your time when the castle is shut. Our The Story of Cornwall covers the wider history and the Tintagel guide covers Cornwall’s other great rock.
Table of Contents
- The two rules that catch everybody out
- What it costs, and when it is free
- The causeway, and the tide
- Who owns it, and who lives there
- Doing it in winter, which is better than it sounds
- Practical notes
- FAQ
- References and resources
The two rules that catch everybody out
1. It is closed every Saturday
All year. The Mount’s own FAQ puts it plainly: the island closes every Saturday so that the people who live and work there get a day of rest. If your trip only has a Saturday in it, you cannot go.
This is the single most useful fact on this page and it appears on almost no third-party guide.
2. The castle and gardens shut for the winter
For the 2026/27 season the winter period runs 1 November 2026 to 19 March 2027, and the Mount’s own castle page states the castle reopens on 21 March 2027. The gardens close earlier still — the season ends in early September.
Boats stop too. They run roughly 15 March to 30 October, so in winter the causeway is the only way across, which makes the tide the thing your whole day hangs on.
A caution on the Mount’s own website. Its pages contradict each other in places — one castle page carries an undated line about being open Sunday to Friday, which reads like current opening but sits alongside the closure notice. Trust the dated access calendar, and if your plan depends on it, phone.
What it costs, and when it is free
| Season | What you get | Cost |
|---|---|---|
| Winter (roughly mid-September to the end of April) | Harbour, village, shops, café and gallery. Causeway on foot | Free. No ticket required |
| Summer season | Castle, gardens, boats, the lot | Castle admission around £21 for an adult |
The free winter access is the part people do not know, and it changes the maths entirely. You can walk out to a tidal island, look at a harbour and a village that has been inhabited for centuries, have a coffee, and walk back, for the price of parking.
Parking is not free. The Mount is clear that parking tariffs apply to all visitors, and you park in Marazion rather than on the island — there are no cars on the Mount at all. Our parking guide covers how Cornish parking works.
The causeway, and the tide
The granite causeway is the reason the Mount is the Mount, and it is also the constraint on your day.
- It is open for about four hours a day, depending on tide and weather, and the times shift daily. There is no fixed opening time to memorise.
- Allow about fifteen minutes to walk its length.
- Check the Mount’s Causeway Calculator for your specific date before you commit to anything. It is on their walking page and it is the only reliable source for your day.
- It is cobbled, uneven and genuinely tricky underfoot. Sensible shoes, not fashion boots, and think carefully if anyone in the party is unsteady.
- Do not attempt it outside the posted window. The Mount’s own warning is blunt: when the causeway is submerged the path is uneven, visibility is limited, currents are strong and the sea rises quickly.
And it can close for weather. Strong winds or rough seas will shut the island, with 24 hours’ notice where possible. One line from their FAQ is worth quoting for the tone of the place: they will not close just because it is raining. Our weather guide and storm watching guide cover what a Cornish winter actually throws at that stretch of coast.
Who owns it, and who lives there
More interesting than most castle histories, because it is still going on.
- It began as a religious site, granted by Edward the Confessor to the Benedictines of Mont St Michel in Normandy — the Mount’s larger French near-twin, which it resembles closely enough that the two are routinely confused in photographs.
- The St Aubyn family bought it in 1659, after Colonel John St Aubyn had been involved in its capture during the Civil War, and their descendants still live in the castle.
- In 1954 the 3rd Baron St Levan gave most of the Mount to the National Trust with an endowment, while the family retained a 999-year lease on the castle and the right to run the visitor operation. That unusual arrangement is why it does not feel like a standard Trust property.
- Around thirty people live on the island, which is the fact that explains the Saturday closure. It is a community, not a monument.
On the earlier history, a warning. Published accounts disagree sharply on the early dates — on when the first church was built, when the priory was founded, and on what happened to it in the medieval period. We are not going to pick a side. Treat any confident single date you read about the Mount before 1600 with suspicion. Our The Story of Cornwall covers the period more carefully, and the maritime heritage guide covers the working sea around it.
Doing it in winter, which is better than it sounds
The castle being shut removes the queue, the ticket and most of the people, and leaves the thing that was always the best part: the walk out.
- Go for the causeway, not the castle. Walking to an island on a road that is under the sea twice a day is the experience. In low winter light, with nobody on it, it is considerably better than in August.
- The village and harbour are free and open. A café, a shop, a gallery, and a handful of houses on a rock.
- Marazion itself is worth the time — a proper town with a year-round population rather than a seasonal strip, and the view back to the Mount from the beach is the one on the postcards.
- Pair it with Penzance, ten minutes away, which has the branch-line station, galleries and places open in winter. Our branch lines guide and where to stay guide cover getting there and basing yourself.
- Check the lights dates if that is the draw. Marazion’s Christmas lights switch on in early December, so a November visit will be too early for them.
Our off-season guide covers what else is open across the county, and our November guide and March guide cover the months at either end of the closure.
Practical notes
- Check three things in order: the day of the week (not Saturday), the season (castle or no castle), then the causeway time for your date.
- Phone if it matters. The Mount’s line is open Monday to Friday, 10am to 2pm, and the people answering it know more than any website.
- There are no cars on the island. Everything arrives on foot or by boat in season.
- It is steep. The castle, when open, is reached by a cobbled climb, and the island is not a flat stroll. Check the Mount’s access information if that is a factor.
- Do not confuse it with Mont St Michel. A surprising amount of online imagery labelled St Michael’s Mount is the French one.
- If the island is closed and you have driven out, Marazion beach, Penzance and the Lizard are all close. Our cosy pubs guide and Eden Project guide cover wet-weather alternatives, and the great gardens guide covers the far west’s gardens.
FAQ
Q: Is St Michael’s Mount open on Saturdays?
A: No. The island closes every Saturday, all year, so that the people who live and work there have a day of rest. If your trip only includes a Saturday, you will not be able to visit.
Q: Is St Michael’s Mount open in winter?
A: The island is, but the castle and gardens are not. For the 2026/27 season the winter period runs from 1 November 2026, with the castle reopening on 21 March 2027. In winter you reach the island on foot across the causeway at low tide, and the harbour, village, shops and cafe are free to visit.
Q: How much does St Michael’s Mount cost?
A: In winter, nothing for the harbour, village, shops and cafe, with no ticket required. In season, castle admission is around £21 for an adult. Parking in Marazion is charged at all times of year.
Q: Do the boats to St Michael’s Mount run in winter?
A: No. Boats run roughly from 15 March to 30 October. Outside that, the causeway at low tide is the only way across, which makes checking the tide essential.
Q: How long is the causeway walk to St Michael’s Mount?
A: About fifteen minutes each way. The causeway is open roughly four hours a day depending on tide and weather, and the times change daily, so check the Mount’s Causeway Calculator for your date. It is cobbled and uneven, so wear sensible shoes.
Q: Who owns St Michael’s Mount?
A: The National Trust owns most of it, following a gift from the 3rd Baron St Levan in 1954 with an endowment. The St Aubyn family, who bought the Mount in 1659, retained a 999-year lease on the castle and still live there, and they run the visitor operation.
Q: Can St Michael’s Mount close at short notice?
A: Yes. Strong winds or rough seas can force the island to close, with 24 hours’ notice given where possible. Rain alone does not close it.
References and resources
- St Michael’s Mount — plan your visit: stmichaelsmount.co.uk
- St Michael’s Mount — walking the causeway: stmichaelsmount.co.uk
- St Michael’s Mount — FAQs: stmichaelsmount.co.uk
- National Trust — St Michael’s Mount: www.nationaltrust.org.uk
