Portchester Castle from Hayling Island: Roman walls, Norman keep and dogs welcome near Sandy Point

Portchester Castle stands at the top of Portsmouth Harbour, about 14 miles, or roughly 30 minutes by car from Wittering Sands, our exclusive-use house at 14 Wittering Road, Hayling Island PO11 9SP. You drive up the island, over Hayling Bridge and west along the A27, and the castle is on the south side of Portchester, just off the road.

It is one of the easiest half days out for a group. There is a Roman fort to walk around, a Norman keep to climb, a lot of open grass for children and dogs, and some of the most surprising stories of any castle on the south coast. This guide covers what you will see, dogs, practical tips and getting there.

What is Portchester Castle?

Portchester began as a Roman fort, one of the coastal forts known as the Forts of the Saxon Shore, built in the 3rd century to defend Roman Britain against Saxon raiders. English Heritage, which looks after the site, describes it as the best-preserved Roman fort in northern Europe, and the only one whose entire defensive circuit survives with little altered from when it was built. Coins found on the site date it to after about AD 268, and it may have been founded by Carausius, the commander of the Roman fleet in the Channel.

The walls have been in use ever since. In 904 the Bishop of Winchester gave the fort to King Edward the Elder, and it became a fortified Saxon burh against Viking attack. After the Norman Conquest a castle was built in one corner of the fort, and the great Norman keep was raised in the 12th century. Richard II rebuilt the inner courtyard as a small royal palace in the 1390s.

Medieval kings used Portchester to gather their forces before crossing the Channel. Edward III stayed here in 1346 before Crécy, and in 1415 Henry V launched the invasion of France from here that ended in his victory at Agincourt on 25 October. While he was at Portchester, a plot to depose and murder him, known as the Southampton Plot, was uncovered. Elizabeth I held court here in 1603.

What can you see and do there?

• Climb the keep: the keep is about 30 metres, or 100 feet, high, and from the top you get wide views across Portsmouth Harbour and the Solent. The stone stairs inside are steep, narrow and winding, and the wooden steps are very steep, so take it slowly with younger children.
• The exhibition: the ground floor of the keep has displays on the history of the castle and Portchester village, with finds dug up on site from the Roman, Saxon, medieval and Napoleonic periods. There is a ramp into the exhibition.
• The prisoners of war: from 1665 Portchester was used to hold foreign prisoners of war. During the French Revolutionary and Napoleonic wars, from 1793 to 1815, it held up to 8,000 prisoners at any one time. Among them were around 2,000 mainly black and mixed-race prisoners brought from the Caribbean in 1796 after being captured while fighting on St Lucia, and an installation at the castle tells their story.
• The prisoners' theatre: in 1810 French prisoners turned a room in the keep into a theatre, where local people came to watch them perform. English Heritage calls it a remarkably well-preserved Georgian theatre, and you can still see it inside the castle.
• The parish church: an Augustinian priory was founded inside the Roman walls in 1128. The community moved to nearby Southwick in 1150, but its church still stands inside the fort as Portchester's parish church.
• A walk round the walls: there is an outer walk that circles the castle, with views of the harbour and coastline. Look for the Roman brick and flint in the walls as you go.

For children, English Heritage runs a World Builder trail at Portchester, one of four at its sites, which invites them to make up their own legend as they explore.

Is it good for a group picnic?

Yes, and this is one of the things that makes it work so well for a big group. The walls enclose more than nine acres of grass in the outer bailey, and English Heritage says ball games and kites are allowed. The whole outer bailey is ideal for a picnic, and there are picnic benches and a grass area in the inner bailey too. Barbecues, tents and gazebos are not allowed, and smoking, vaping and naked flames are not permitted anywhere on site.

A small selection of snacks and hot and cold drinks is sold on site, and the gift shop sells snacks, toys, souvenirs and guidebooks. For a proper lunch, we would bring a picnic from the house.

Can you take a dog?

Yes. English Heritage says dogs on leads are welcome throughout the site. There are two water taps, one by the church and one on the drawbridge, and dog bins on site. With a dog that loves a run, the open grass inside the walls is the draw, but keep the lead on and watch for the moats, which can hold deep water and have steep banks.

If you want more dog days out from the house, our dog-friendly Hayling Island guide covers walks from the door, and our Fishbourne Roman Palace guide is another Roman site where well-behaved dogs are welcome.

What should you know before you go?

• Opening times: English Heritage currently lists the castle as open daily, 10am to 5pm, with last entry at 4.30pm. Hours can change through the year and over holidays, so check the English Heritage page before you set off.
• Tickets: you need a ticket for the castle itself. English Heritage members go free, and booking online by midnight the day before your visit gets a discount. Tickets are valid all day. Visitor guides note that you can walk into the large area inside the Roman walls without a ticket.
• Parking: there is charged parking about 200 metres from the castle entrance, not managed by English Heritage. There are some disabled spaces in the public car park.
• Toilets: there are no toilets inside the castle. The nearest are in the large car park outside the walls, so plan a stop on the way in.
• Access: the drawbridge and level grass give wheelchair access to the inner bailey, and the ground floor of the keep and the exhibition can be reached by a ramp. There is no access above the ground floor. Pushchairs are welcome on the ground floor levels and can be left in the inner bailey.
• Low light and uneven ground: the keep is dimly lit in places, and there are low ruined walls, old steps and uneven ground across the site. Stairs get slippery when wet.
• Drones: English Heritage does not allow drone flying from or over its sites.

The clocks go back on Sunday 25 October 2026, the anniversary of Agincourt, so later in the autumn the light goes earlier. A morning visit leaves time to get back to the house before dark.

How do you get there from Hayling Island?

• By car: drive north up the A3023 and over Hayling Bridge, then follow the A27 west. English Heritage says the castle is on the south side of Portchester off the A27, near Junction 11 of the M27. The postcode is PO16 9QW (Church Road, Portchester).
• By bus and train: Stagecoach 30 and 31 run between the island and Havant, with a stop at Sandy Point Reserve. From Havant, Southern trains towards Southampton call at Portchester, which English Heritage says is about 1 mile from the castle. At the time of writing those Southern trains do not call at Portchester on Sundays. First bus service 3 stops within a quarter of a mile. Check Stagecoach, First and National Rail times before you travel.
• By bike: English Heritage points cyclists to Sustrans and the National Cycle Network for route planning.

With a group of nine and a picnic to carry, a car or two is much the easiest option.

What else could you combine it with?

Portchester sits at the top of the same harbour as Portsmouth, so it pairs well with a harbour day. Our Portsmouth harbour day trip guide covers the waterfront and the Historic Dockyard. If the group enjoys the Roman side, Fishbourne Roman Palace is a similar drive east of the house. For more autumn day-out options, our October half-term guide and November weekend guide have further suggestions, and our Around Hayling guide covers beaches, pubs and walks closer to home.

What are the stay details?

Check-in is from 4pm and checkout is by 10am. Wittering Sands sleeps up to nine across four bedrooms and five beds, with 3.5 bathrooms. Up to two well-behaved dogs are welcome at the house, with no extra pet fee, kept off beds and sofas, and parking is available for four cars. Children of all ages are welcome, babies and toddlers included, and a travel cot and highchair are available on request, so just ask when you book. The minimum stay is 2 nights, and some dates may require longer; the booking calendar shows the minimum for your dates. Bookings need at least 48 hours' notice.

Rates vary by season and length of stay. The live calendar shows the current figure for your dates; this guide does not indicate availability.

How do you book?

Check the live booking calendar for current dates and pricing. If you want to talk through the group, dogs or travel arrangements, get in touch.

Opening times, ticketing, dog rules, parking arrangements and bus and train timetables can change. Check English Heritage, Stagecoach, First and National Rail before you travel.