Built just two years before nearby 1933, the still-functioning Shanghai General Post Office must rank as among the world's finest: it's baroque clock tower alone (which you can get close to from the free-to-enter roof garden) is something of a city landmark. (Those in the know use the garden for secret picnics, taking full advantage of a five-star-worthy view of the Pudong skyline, just across the river.)

The second of the building's four floors is the post office proper, and also the jumping-off point for a surprisingly engaging display on the history of mail in China: from pictures of messengers on horseback, to decommissioned freight trains, and even a postal aircraft suspended in the building's rather beautiful atrium. Stamp collections, uniforms, and an imagined "Future Postal Service" round out the display. All in all, certainly one of the more unexpected delights in the city.