Hereford Cathedral
Built of local red sandstone, Hereford Cathedral is a treasure trove of historical artifacts, including Mappa Mundi, the largest surviving medieval map, and Britain's largest chained library (a sort of medieval security system), which has its locks and chains intact. The cathedral retains a large central tower, and while much of the interior was restored in the 19th century, 11th-century Norman features remain, including intricate stone carvings. There are exquisite contemporary stained-glass windows in the Audley Chapel and a 12th-century chair that is one of the country's oldest pieces of furniture and was reputedly used by King Stephen (1092–1154).
The Mappa Mundi is the biggest attraction, though. Drawn in about 1300, it’s a fascinating glimpse of how the medieval mind viewed the world: Jerusalem is shown dead center, the Garden of Eden at the edge, Europe and Africa are the wrong way round—and, of course, there are no Americas. Besides land masses, the map details 500 individual drawings, including cities, Biblical stories, mythical creatures, and images of how people in different corners of the globe were thought to look. The map is outside the Chained Library, which contains some 1,500 books, among them an 8th-century copy of the Four Gospels. Chained libraries, in which books were attached to cupboards, are rare: they date from medieval times when books were as precious as gold. The cathedral also holds a copy of the 1217 revision of Magna Carta. Tours of the cathedral (without the library and Mappa Mundi, which require an extra fee, though volunteers can answer your questions) run daily (except Sundays). Garden tours run in summer and tower tours on Wednesdays and Saturdays.