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Despite its sprawling coastline, Essex isn't as well-endowed with castles as its neighbours in Kent or Sussex. That said, there are a few fortifications sprinkled around the country, for casual day trippers and dedicated historians alike.
Colchester Castle
Colchester was once the capital of England, making Colchester Castle a sort-of former Tower of London — though with fewer crowds and far less bling. It's situated in Colchester town centre, making it easier to visit by train than some of England's more rural fortresses.
These days, it's owned and managed by Colchester & Ipswich Museums, and is run more like a museum than a castle, showcasing Colchester's history from the Celtic kings onwards. Objects of particular interest include the Fenwick Hoard, a stash of Roman jewellery which was buried to keep it safe from Boudica's army.
Colchester Castle is the largest Norman keep in Europe, and is built on the foundations of the Roman temple of Claudius. Join one of the daily guided tours to go down into the Roman vaults and prisons, and up on the castle roof. There's plenty for kids, including dressing up activities, and a chance to steer a Roman chariot.
Read our full guide to visiting Colchester for other things to see and do in the area.
Hedingham Castle
If you want a proper day out at a castle in Essex, with bells, whistles and knights in shining armour, Hedingham Castle is the place to head.
It's part of the Historic Houses scheme, which is similar to National Trust and English Heritage, and is located in the village of Castle Hedingham. The building is an imposing, square fortress with five floors of history to explore, all joined by atmospheric spiral staircases.
Away from the building itself, the grounds offer plenty to fill a day out. Wander through landscaped gardens, ogling ramparts that are over 1000 years, and check out the views across Essex from the top of the motte. Look out for special events throughout the year, including jousting tournaments, shows and theatre productions.
Mountfitchet Castle and Norman village
OK, we'll level with you — Mountfitchet Castle isn't the authentic, ancient deal; it's a reconstruction. The current incarnation was only recalled to life after the ruins of a former motte and bailey castle were purchased in the 1970s. The owner set about reconstructing the original with as much historical accuracy as possible, opening the results to the public in 1985.
Today you can visit the only wooden motte and bailey reconstruction on its original site anywhere in the world, along with a simulacrum of a Norman village. The result is a part-castle, part-adventure playground vibe — animals which would have been farmed by the Normans roam freely around the site, and visitors can wander into the houses and have a look around.
While you're there, take a look at the House on the Hill Toy Museum on site — with 70,000 toys on display, it served us a hefty dose of nostalgia and left us grinning from ear to ear.
Castle ruins in Essex
Not all Essex castles are in such excellent shape. These ruins and partial ruins survive today, and may be of interest to the most dedicated castle explorers.
Hadleigh Castle
Hadleigh Castle is owned and managed by English Heritage, but don't turn up expecting tea rooms and a gift shop — it's a ruin (albeit a beautiful one) in a field, with no visitor facilities. That's not to say it doesn't have its historical merits — a barbican and two drum towers partially survive from the 1360s, having later been used in Georgian times to look out for smugglers in the nearby Thames Estuary.
Walden Castle
Walden Castle in Saffron Walden was built in the 1140s, though much of its impact can still be seen today — the streets in the town are shaped by the outline of the castle bailey. As for the castle itself, it's Grade-I listed, with remnants of the tower keep and parts of the exterior walls surviving. Much of the masonry was lost to theft over the centuries.
Essex may be lacking in castles, but do check out Naze Tower in Walton on the Naze, a Grade-II* listed clifftop folly on the North Essex coast.