Boston By Foot has been walking people through this city for decades, and its guides are the secret: a trained corps of volunteers — teachers, engineers, architects, history obsessives — who lead tours because they love the material. Routes fan out across downtown, Beacon Hill, the North End, and Back Bay, reading the city through its brownstones, burying grounds, and Bulfinch-era landmarks.

The nonprofit’s catalog runs from big-picture architecture-and-history walks to sharply specific themes — Victorian design, Art Deco, literary Boston — with public tours running daily and weekly from spring through late fall and private tours available year-round. It suits visitors doing Boston properly and, just as much, locals who’ve walked these blocks for years without knowing what they’re looking at. Book ahead; registration closes shortly before each departure.