The leaning ruins
Walls blown up in 1646 and still standing at impossible angles on the hilltop.
In 1646 Parliament decided this castle was too dangerous to leave standing, so it packed the walls with gunpowder and blew them up. What survived is what you see today: a great keep split from top to bottom, walls leaning at angles that defy sense, whole sections that slid down the slope and froze mid-fall. That is precisely why Corfe is worth the drive. England has plenty of ruins; very few of them still look as though they are collapsing. The history runs deep. The Normans began it straight after 1066, Henry I added the keep around 1100, and King John used it as a treasury and a prison. The story the guides love, though, is Lady Mary Bankes, who held the castle through two Civil War sieges, in 1643 and 1645, and lost it only when one of her own officers betrayed her. It now belongs to the National Trust: non-members pay £15 per adult off-peak and £16 on peak dates (Easter, bank holidays, half-term and the summer holidays), children aged 5-17 roughly half that, and a family ticket for two adults and up to three children comes to £37.50-40. No advance booking is needed unless you are a group of 15 or more. Manage expectations. The site is small, and the climb to the top is a steep, uneven path of grass and stone - no good for pushchairs or wheelchairs - but children over five love it, because this is a place for scrambling and running rather than filing past display cases. An hour to ninety minutes is plenty, then walk down into the village, built entirely of grey Purbeck stone and very much part of the point. The best photograph is not from inside the walls at all but from the lane west towards Church Knowle, or from East Hill at sunrise. From Bournemouth it is about 45 minutes by car via Poole and Wareham; the National Trust car park sits opposite the castle (free for members, pay machines or the JustPark app for everyone else) and fills early on summer weekends. The nicer option with children, when the railway is running, is to park at Norden and ride the Swanage Railway steam train one stop to Corfe Castle station. The Purbeck Breezer 40 bus from Poole also gets you there in about an hour. Open daily year-round: 10:00 to 17:00 or 18:00 in summer, stepping down through the autumn to 10:00-16:00 in winter, closed only on 25-26 December.
Walls blown up in 1646 and still standing at impossible angles on the hilltop.
Park at Norden and arrive by real steam train; children do not forget it.
A grey Purbeck-stone village under the walls, and the best photo from the Church Knowle lane.
The Square, Corfe Castle, Wareham BH20 5EZ
With children over five, yes: the hill is made for scrambling and the steam train from Norden turns it into a proper day out. With a baby in a pushchair it is harder; the climb is steep grass, so you may settle for the village and the view from outside, then carry on to Swanage beach or Old Harry Rocks fifteen minutes further.
No booking is needed even in summer, except for groups of 15 or more, though the car park fills early on weekends. The castle itself takes no more than ninety minutes, so pair it with Swanage, Studland or Wareham to make a full Purbeck day.