8. Edinburgh Castle, Edinburgh, Scotland

This magnificent castle is typically medieval, perched atop a rocky crag, giving it an amazing vista of Scottish hills. But inside the empty halls and narrow streets of Edinburgh, there are the echoes of the dead. At least, that’s what has been reported. Hot spots for specters include the castle’s prison cells, the South Bridge vaults and Mary’s King Close, a disused street used to quarantine and eventually entomb victims of the plague. There are also reports of ghost dogs, a headless drummer, and the bodies of prisoners taken during the French seven-year war and the American War of Independence.