Hoanh Son Quan, named 'sky gate' by locals, is where visitors check in when crossing Ngang Pass, on the border of Ha Tinh and Quang Binh provinces. 

Built from bricks and stones in 1883, during the reign of Emperor Minh Mang (1820-1841), Hoanh Son Quan helped control entry and exit at Ngang Pass. The ‘sky gate’ is situated at the highest point of Ngang Pass. It is commonly held that the sky can be touched when reaching Hoanh Son Quan.

The entrance is 4 m high, with a total structural width of 30 m.

Visitors have to scale steep steps covered in wild grass to reach the gate.

Dozens of travelers stop along 1A Highway to visit Hoanh Son Quan each day.

“On the weekend, my friends and I often travel to Ngang Pass. At Hoanh Son Quan, we could breathe the fresh air of both Ha Tinh and Quang Binh provinces. This place is so spacious, comfortable and relaxing,” said Tran Thu Ha, 27, from Ha Tinh.

The old Chinese lettering above the entrance has cracked due to weathering.

The gate’s moss covered ceiling has been well worn by the passage of time.

Hoanh Son Quan lies amid a grove of wild trees.

Ky Nam Commune in Ky An Town of Ha Tinh Province lies to the north of the gate.

And to the south, Quang Dong Commune in Quang Trach District of Quang Binh Province.

Vandals have marked many of the gate’s inner walls, causing irreparable damage in some areas.

Because it’s not clear Ha Tinh or Quang Binh owns the relic, no organization is willing to take responsibility for its maintenance.