Tibetan Buddhism heritage site, the Potala Palace, saw 1.45 million tourists in 2017, up 5.8 percent year on year, sources with the palace administration said Wednesday.

The number of visitors to the palace, in Lhasa, capital of Tibet Autonomous Region, has surged rapidly. In 2015, only 900,000 tourists visited the palace, according to its administration.

To protect the site, the administration has set the limit of a maximum of 5,000 tickets per day during high season, and visitors have to reserve tickets in advance and are given a specific entrance time.

Dozens of scalpers have been punished for reselling reservation tickets, according to Lhasa police.

The Potala Palace, first built in the seventh century, was put on the World Cultural Heritage site list in 1994.