For history & culture, Mapparium (Mary Baker Eddy Library) is hit or miss.
A one-of-a-kind oddity — standing inside a glowing inside-out world map where the acoustics make a whisper carry across the room is genuinely delightful and unexpected. The catch: it's a brief, single-trick attraction inside the Christian Science complex, the map is frozen in 1935 geopolitics, and it's a 20-minute curiosity rather than a half-day.