Greyfriars Church, built circa 1620 on the site of a medieval monastery, was where the National Covenant, declaring that the Presbyterian Church in Scotland was independent of the monarch and not Episcopalian in government, was signed in 1638. The covenant plunged Scotland into decades of civil war. Informative panels tell the story. Never mind all this, though—the real attraction here is the sprawling, hillside graveyard, surely one of the most evocative in Europe. Its old, tottering, elaborate tombstones mark the graves of some of Scotland's most respected heroes and despised villains. Some of the larger tombs are arranged in avenues; a few are closed off, but others you can wander. It's a hugely atmospheric place to explore, especially at twilight. Look out for two rare surviving mortsafes, iron cages erected around graves to prevent the theft of corpses for sale to medical schools, a grisly nuisance in the early 1800s. Nearby, at the corner of George IV Bridge and Candlemaker Row, stands one of the most photographed sites in Scotland: the Greyfriars Bobby statue.