BEIJING, July 21 (Xinhua) -- China will confirm and publish the altitude of 59 famous mountains in the coming two years, as a step to clean up the country's still messy geographical data.

The 59 mountains, all renowned tourist destinations and national reserves, include the World Heritage Site Wuyi Mountain in Fujian Province and snow-capped Yulong Mountain in Yunnan Province.

The State Bureau of Surveying and Mapping (SBSM) said Saturday that experts are measuring mountains with Global Position System (GPS) and other high-tech devices.

The bureau will announce the altitude of 30 mountains in 2008 and that of the rest will be announced in 2009.

"Elevation data for many mountains in China are currently inconsistent and inaccurate, sometimes the difference can be as much as 100 meters," said Li Weisen, SBSM's deputy director.

Li attributed the inaccuracy mainly to technological and equipment limits, saying the demand for accurate, standardized geographical data has increased in recent years.

A total of 78 mountains located in key national scenic spots have been put on the SBSM's significant geographic information and data list, taking into account their fame and influence, public function and their bearing on national security.

In April 2007, the SBSM announced the altitude of 19 mountains after nine months of surveying.

According to the Chinese laws, no organizations or individuals are allowed to issue important geographic data without verification and authorization of the SBSM.

Unauthorized publication and incorrect use of important geographic information and data will be subject to punishment.