Indian and Chinese officials have reopened the Silk Road's Nathu La pass, high in the Himalayas, 44 years after it was closed by war.
The opening ceremony marked the latest in a string of measures India and China have taken to improve ties and end years of mutual suspicion rooted in the border war of 1962.
The 4,300 metre high (14,000ft) pass lies between India's north- eastern state of Sikkim and Tibet.
Sikkim's chief minister, Pawan Kumar Chamling, and Champa Phuntsok, the Chinese-appointed leader of Tibet, shook hands then cut a red ribbon, to the cheers of the gathered dignitaries, soldiers.
"The opening of the border pass at Nathu La after 44 years marks the beginning of a new era in Sino-Indian relations," Mr Phuntsok said. "I hope the border people of these two great nations will benefit from this."
Military bands played and the festivities were not dampened by a heavy mist that swirled between the mountain peaks, and the near-freezing drizzle that fell on the participants, crowded into the small open space that makes up the border.
Troops from both sides mixed freely, helping to set up the event after years of staring at each other with mutual suspicion across a barbed-wire border. Many Chinese soldiers took souvenir photographs.Reuse content