A road will finally reach the last two towns in southwest China's Tibet Autonomous Region this year, according to a regional official.

"All towns in the region will have highway access in 2017," said Sonam Chosphel, an official with Tibet Transport Department. "Gyalasa and Gandeng in Medog County are the last two roadless towns."

Medog is China's last roadless county, and ended its isolation from the outside in 2013 with the opening of a highway.

Last year, Tibet invested 40 billion yuan (5.8 billion U.S. dollars) in transport construction, up 90.7 percent year on year, and its total length of operating highways reached 82,000 km.

"This year, the region will spend 52 billion yuan building or upgrading high-grade roads, national or regional key highways, and rural roads, with operating highways surpassing 90,000 km," Sonam Chosphel said.

The roads linking the Medog County seat to the two towns began construction in 2015 and will be completed at the end of the year.