China has confirmed and published the altitude of 19 of its most famous mountains, as a step in cleaning up the country's still messy geographical data.

The 19 mountains, all renowned tourist destinations, include the well-known "Five Sacred Mountains" -- Mount Tai in east China's Shandong Province, Mount Heng in central China's Hunan province, Mount Hua in northwest China's Shaanxi Province, Mount Heng in north China's Shanxi province and Mount Song in central China's Henan Province.

Mount Tai, located near Confucius' birthplace and considered the holiest of the five, is 1,532.7 meters high, according to statistics released jointly by the State Bureau of Surveying and Mapping (SBSM) and the Ministry of Construction on Friday.

Up until now, the height of Mount Tai appeared as 1,545 meters, 1,536 meters or 1,533 meters -- depending on which textbook or tourist guide you were reading, or what TV documentary you were watching.

"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, at a press conference in Beijing.

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

The other four sacred mountains, Mount Heng (Hunan), Mount Hua, Mount Heng (Shanxi) and Mount Song, measure 1,300.2 meters, 2,154.9 meters, 2,016.1 meters and 1,491.7 meters, respectively.

"These figures are official scientific data," Li said.

They can be used by the government for administrative management, news reporting and teaching, he said.

The SBSM and Ministry of Construction will soon send workers to remove the old height signs and stick up new markers in selected places on the mountains.

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.

"The mountains, usually places of both scenic beauty and historical interest, bear testimony to China's thousands of years of civilization," Li explained.

The surveying of the first batch of 19 mountains began in July 2006 and lasted until March 2007.

In 2005, Chinese scientists showed that the summit of Mount Qomolangma, known as Mount Everest in the west, is 8,844.43 meters, 3.7 meters shorter than the figure measured three decades ago.

Li also said that no organization or individual should publish "significant geographic information and data" without authorization.

Significant geographic information and data refer to positions, elevations, depths, areas and lengths of important natural and cultural geographic entities within China's territorial air, land and waters, he explained.

The SBSM is working on a plan to gradually verify and release some important geographic information and data, including the lengths of national land boundaries and coastline, areas of territorial land and sea as well as the quantity and areas of islands and reefs.

"We are making technical preparations for the publication of the elevation of China's lowest land spot, Aydingkol Lake, the length of the Great Wall and data about some other famous mountains and rivers," Li said.

He stressed that random release of important geographic information, which is against related laws and regulations, may not only distort the figures and confuse the public, but also pose a threat to national security and territorial integrity.

He cited the unauthorized building of a "national center tower" in northwest China's Gansu Province in September 2000.

"The tower was set up to mark the so-called geographic center of China's land territory, but its location was selected after only rough calculation under the circumstances that the national boundaries had yet been fixed," he said.

"Organizations or individuals that want to publish important geographic information must apply in writing for approval from the SBSM ," he noted.

Unauthorized publication and incorrect use of important geographic information and data will be subject to harsh punishments, he added, without elaborating.