KUNMING, March 10 -- "Flying doctors" in southwest China's Yunnan Province crossed the Nujiang River along a rickety zip line for nearly 30 years.

The zip line in Lamadi Village, Nujiang Lisu Autonomous Prefecture had no safety apparatus, not even a life jacket.

"Check the pulley and don't look back," doctor Deng Qiandui recalled.

Elsewhere across the world, zip lining is popular with thrill seekers. However, in some villages perched on mountainsides in China's western areas, it is the quickest link to civilization.

Three years ago the local government built a bridge across the river's deep ravine, making trips in to town much easier -- and safer.

In his government work report delivered earlier this month, Premier Li Keqiang pledged to replace all zip lines with bridges this year.

According to a national plan, from 2013 to 2015, about 290 bridges will be built in seven western provinces, half of them in Yunnan, benefiting 958,000 residents.

Nujiang prefecture has three vast rivers, to meet Li's deadline, local authorities have nine months to finish building 17 bridges, a massive task, even without taking into consideration that all the materials must be carried along the zip lines.