The watchtower of Deshengmen is one of two preserved arrow castles of the old Beijing inner city wall. It was well-known as the Military Gate, because it was the main gateway for the imperial army to go to the North. When the national hero Yu Qian of the Ming dynasty defended Beijing in 1449, the main battlefield was just outside Deshengmen. In 1664, Li Zicheng, the leader of the insurrectionary army, led his troops into the city through Deshengmen as well. The watchtower of Deshengmen is 31.9 meters high, sitting on the grand platform of the gate. It is a four-storey building with 7 rooms, and has 82 ports for shooting arrows. In October, 1979, the watchtower was listed as a key Beijing cultural heritage protection site. It was renovated and opened to the public in 1980.

In 1993, sponsored by the government, the Zhenwu Temple was built in Deshengmen and the Beijing Ancient Coins Museum was founded there. This museum is specialized in the ancient coins and it is the only museum of its kind in Beijing that is open to the public. It puts on display ancient Chinese coins from different dynasties throughout the year. Some temporary exhibitions are also available. The museum is an ideal place for study and collection of ancient coins.