The next year, Princess Wencheng started the journey to Tibet from the capital Chang'an (the present Xian City). To smooth the trip, Emperor Taizong commanded the officials to build roads, bridges and Buddhist chapels en-route and carve out roadways. Songtsen Gampo welcomed the princess for himself at the headstream of the Yellow River (Zhaling Lake and Eling Lake). Then he accompanied the princess to the capital of his kingdom-Luoxie (present Lhasa) and held the wedding ceremony.
The marriage of Princess Wencheng and Songtsen Gampo was an epochal event during the history of the Ancient Tangbo Road. Since then frequent political and commercial communications between Tang and Tubo began. The road was gradually busy with many embassies and merchants, and developed into a well-known official and trade path. In 709 King Tride Tsugtsen (reigned 703-755) of Tubo proposed another marriage to Tang, and Princess Jincheng was married to him, who also entered Tibet along the Tangbo Road.
Route
The Ancient Tangbo Road extends from Xian to Lhasa, crossing Shaanxi, Gansu, Qinghai and Tibet, with a distance of around 3,000 km (1,864 miles), half of which lies within Qinghai. The road is divided into the eastern section and the western section at Xining, a very important transfer post at that time.
The route runs as follows: Xian City (Shaanxi)-Xianyang City-westwards along eastern section of Silk Road-Long Mountain-Tianshui City (Gansu)-Longxi County-Lintao County-Linxia Hui Prefecture-Bingling Temple/Dahejia –crosses the Yellow River-Guanting Town, Minhe County (Qinghai)-Gushan Town-Ledu County-Xining-Huangyuan County-Riyue Mountain-crosses the Daotang River-Qiaboqia Town (Buddhist Chapel of Princess Wencheng)-Qieji Grassland-Dahe Dam-Hot Spring-Huashi Gorge-Huangheyan-passes by Zhaling Lake and Eling Lake-crosses the Bayan Har Mountains-crosses the Qingshui River, Yushu Tibetan Prefecture-crosses the Tongtian River-Jiegubatang-upstream Ziqu River-Zaduo County-along the Qinghai-Tibet Highway-Dangqu River-Tanggula Mountain Pass-Nakchu (Tibet)-Yampachen-Lhasa.
The Ancient Tangbo Road almost coincides with the Silk Road within Shaanxi and Gansu Provinces, with Qingkang Road (part of 214 National Highway) from Xining to Yushu, and with Qinghai-Tibet Highway from Nakchu to Lhasa. The condition of the road, especially the western section, is very tough and challenging, however, it remains very spectacular natural scenery with primitive cultural relics. Many stories and legends related to the road also make it a most mystical sight to explore.