"Ha Giang Province is a province in northeastern Vietnam. It is located in the far north of the country, and contains Vietnam's northernmost point. It shares a 270 km long border with Yunnan province of southern China, and this is known as Vietnam's final frontier. The provincial capital, also called Ha Giang, is connected by Highway 2 and is 320 km away from Hanoi. The border crossing is at Thanh Thuy, 25 km from the capital, Ha Giang town. It is one of the poorest provinces of Vietnam as it has mountainous topography with the least potential for agricultural development. Like Sapa, the most renowned attraction of Ha Giang is the many grandiose mountains. Although mountains here are not as high as Sapa's mountains and seem not to be steep enough to challenge adventurous climbers, they stand out for extensive area of limestone with unique formation of peaky rocks. The most famous rocky area of Ha Giang is Dong Van Rock Plateau, which is recognized by UNESCO as one of 77 geological parks in the world. Lung Cu Hamlet lying inside Dong Van Rock Plateau is another indispensible destination as it marks the very northern tip of Vietnam by Lung Cu Flag Tower on Dragon Mountain."