Carlisle sits at the meeting point of three rivers — the Eden, the Caldew, and the Petteril — and has spent most of its history as a contested border city between England and Scotland. That contested past left it with some of the finest medieval fortifications in northern England: a castle that has been besieged more times than almost any other in the country, and a cathedral that survived centuries of conflict, fire, and Civil War damage.
The city is the capital of Cumbria, and most travellers who pass through are on their way north to Glasgow or south from Scotland. Worth stopping for: the castle is genuinely impressive, the cathedral's painted ceiling is one of the most beautiful things in the north of England that no one talks about, and Tullie House has one of the best Roman collections in the country — built on finds from Hadrian's Wall, which begins (or ends) not far from here.
The twin towers of The Citadel frame the city's southern entrance, and sections of the city walls still stand, giving a sense of how seriously the border city took its defences.
Carlisle is also the northern terminus of the Settle-Carlisle railway, one of the most scenic rail journeys in England. The most dramatic scenery is further south between Settle and Appleby, but arriving or departing Carlisle by this line is a pleasure in itself.