From Ha Giang town, taking the approximately 150km on the 4C highway back to north-east, visitors will go to Dong Van commune, Dong Van District. Dong Van District is the highest protruding point on the map of the country. From there, continuing to sweep the asphalted road connecting Dong Van to Lung Cu commune for about 26km, visitors will reach the summit Lung Cu.

Lung Cu commune has a total area of 3460 ha with natural nine villages, including: Lo Lo Chai, Seo Lung, Ta Gia Khau, Can Tang, Then Van, Then Pa, Si Man Khan, San Cho, San Sa Phin and a contiguous 16 km border with the People's Republic of China. In all the nine villages of Lung Cu, old Seo Lung is the extreme north pole of Vietnam with very deep Then Van valley on the left and Nho Que small river which originated from Mu Cang - Yunnan – China following to Dong Van – Meo Vac – Ha Giang on the right. In the winter, the weather is very cold and sometimes snowy. The highest temperature in the summer is only about 24 degrees C. It is foggy and rainy almost all the year, so the people have a famous saying: "The land is not flat in three steps and it is is not sunny in three days". The Ethnic minority people in Lung Cu mainly work on terraced fields and burnt-over land for living. Especially, the H’mong and Lo Lo people still preserve the traditional weaving with flax fibers.

Lung Cu probably named after: Long Co (long: dragons; Co: drum) means Dragon Drum. As history records, at the time of Tay Son, Quang Trung Emperor had to put a big drum at the borderland. At that time, the drum-beat was the fastest means of communication. The border post now is placed where the King was placed the drum. Therefore, Lo Lo minority people in Lung Cu now can play well-trained drum which is derived from Dong Son drum in the funerals.

From distances, Lung Cu is very spectacular with three quarters of the land covered with stone, a national flag pole erected on the top of the mountain, which is surrounded with magnificent and majestic mountain forests ...

Coming close, the beauty is clearer: a column erected on the Dragon mountain (Long Son), at the foot of columns carved reliefs with crisp Dong Son drum patterns. The flag of the Fatherland waves in the wind and specifically reflected in the green Lo Lo lake. At an altitude of 1,700 m over the sea level, the column flags Lung Cu surface, concrete body, six items in the same drum patterns, 17m high with horns added flags flew wide distribution 54m2 during the night on the firm asserted sovereign nation.

Observed a little more carefully, visitors will see that there is a large and beautiful cave on halfway of Dragon Mountain. The local people named this Si Man Khan cave.

On 29th January 2010, Dong Van district solemnly held a ceremony to receive the National relic certificate for Lung Cu Flag Tower because of its historic and beauty.