The sea of tiles

Lijiang (simplified Chinese: 丽江市; traditional Chinese: 麗江市; pinyin: Lìjiāng Shì) is a prefecture-level city in the northwest of Yunnan Province, China. It has an area of 21,219 square kilometres (8,193 sq mi) and a population of 1,244,7690 as of 2010 census.

Yunnan (simplified Chinese: 云南; traditional Chinese: 雲南; pinyin: Yúnnán; IPA: [y̌nnǎn] ( listen)) is a province of the People's Republic of China, located in the far southwest of the country spanning approximately 394,000 square kilometers (152,000 sq mi) and with a population of 45.7 million (2009). The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.

Yunnan is situated in a mountainous area, with high elevations in the northwest and low elevations in the southeast. Most of the population lives in the eastern part of the province. In the west, the relative height from mountain peaks to river valleys can be as much as 3,000 m.^{[citation needed]} Yunnan is rich in natural resources and has the largest diversity of plant life in China. Of the approximately 30,000 species of higher plants in China, Yunnan has perhaps 17,000 or more.^{[citation needed]} Yunnan's reserves of aluminium, lead, zinc and tin are the largest in China, and there are also major reserves of copper and nickel.^{[citation needed]} Yunnan has over 600 rivers and lakes, which provide an annual water supply of 222 billion cubic meters.^{[citation needed]} Projected hydropower reserves stand at 103 GW, with an exploitable capacity of 90 GW.^{[citation needed]}

The Old Town of Lijiang (simplified Chinese: 丽江古城; traditional Chinese: 麗江古城; pinyin: Lìjiāng Gǔchéng) is a UNESCO World Heritage Site located in Lijiang City, Yunnan, China.

A UNESCO World Heritage Site is a place (such as a forest, mountain, lake, desert, monument, building, complex, or city) that is listed by the UNESCO as of special cultural or physical significance. The list is maintained by the international World Heritage Programme administered by the UNESCO World Heritage Committee, composed of 21 states parties which are elected by their General Assembly.

The program catalogues, names, and conserves sites of outstanding cultural or natural importance to the common heritage of humanity. Under certain conditions, listed sites can obtain funds from the World Heritage Fund. The programme was founded with the Convention Concerning the Protection of World Cultural and Natural Heritage, which was adopted by the General Conference of UNESCO on November 16, 1972. Since then, 189 states parties have ratified the convention.

As of 2011^[update], 936 sites are listed: 725 cultural, 183 natural, and 28 mixed properties, in 153 States Parties. Italy is home to the greatest number of World Heritage Sites to date with 47 sites inscribed on the list. UNESCO references each World Heritage Site with an identification number; but new inscriptions often include previous sites now listed as part of larger descriptions. As a result, the identification numbers exceed 1200 even though there are fewer on the list.

A roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather. Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous.

In most countries a roof protects primarily against rain. Depending upon the nature of the building, the roof may also protect against heat, sunlight, cold, snow and wind. Other types of structure, for example, a garden conservatory, might use roofing that protects against cold, wind and rain but admits light. A verandah may be roofed with material that protects against sunlight but admits the other elements.

The characteristics of a roof are dependent upon the purpose of the building that it covers, the available roofing materials and the local traditions of construction and wider concepts of architectural design and practice and may also be governed by local or national legislation.

Population density (in agriculture standing stock and standing crop) is a measurement of population per unit area or unit volume. It is frequently applied to living organisms, and particularly to humans. It is a key geographic term.

For lists of World Heritage Sites in Asia, see:

This is a list of UNESCO World Heritage Sites in China. China has 41, ranking third in the world. China ratified The Convention Concerning the Protection of the World Cultural and Natural Heritage on December 12, 1985. These sites comprise some of the most essential part of China's valuable and rich tourism resources.