Darkmoor

Darkmoor is a wild, windswept place somewhere in England (several sources say the North East, though at least one possibly unreliable account places it within an hour's travelling from London) which is the location of several notable places in the Marvel UK universe, including the Darkmoor Research Centre (run by Hugo Travis), as well as Darkmoor Prison (where the supervillain Hurricane was imprisoned for some years) and Darkmoor Castle. In fact, there may even be more than one "Darkmoor Castle"; one such structure, supposedly the ancestral home of Lord Rupert Kemp, the Black Baron, was burnt down several years ago but another castle, which had supposedly been in the Haldane family for years, is the home of Dark Angel. The most significant thing about Darkmoor, though, is undoubtedly the ancient circle of standing stones near the Research Centre, a site of magical power which connects Darkmoor to the mystic realm of Otherworld. It was here that Merlyn and the Lady of the Northern Skies asked Brian Braddock to choose between the Sword of Might and the Amulet of Right, which led to his becoming Captain Britain. The Captain has seemingly had some strange connection to Darkmoor ever since, always being drawn back there eventually no matter how far or to what strange worlds he wanders. It's a forbidding place, but a powerful and magnetic one. We'd probably hear a lot more about it, if only people could agree on where it is.