China's northernmost post office is a small but well-known attraction in Beiji Village, operating year-round and offering a commemorative stamp that marks the northernmost postal point in China. You can post a card or letter from here with a cachet that identifies the latitude and the date, which makes it a popular stop for travelers who collect such things — and for Chinese tourists who want a tangible proof of having reached the edge of the country.
The post office also stamps passports and commemorative cards with a special northernmost-point seal, which has become enough of a draw that the lines can be long in summer. In winter the operation is much quieter, and the staff are notably patient with travelers who arrive half-frozen and need a moment to warm up before handling a pen.