Tourists visit the obo, which is a heap of sand, stone or earth laid out as a road marker or boundary and is also worshipped as habitation of spirits by Mongolians, at Hulun Buir grassland, north China's Inner Mongolia Autonomous Region, on July 6, 2012. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Photo taken on July 6, 2012 shows yurts at Hulun Buir grassland, north China's Inner Mongolia Autonomous Region. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Photo taken on July 6, 2012 shows tourists and yurts at Hulun Buir grassland, north China's Inner Mongolia Autonomous Region. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Photo taken on July 7, 2012 shows cole flowers at Hulun Buir grassland, north China's Inner Mongolia Autonomous Region. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Sheep graze at the Hulun Buir grassland, north China's Inner Mongolia Autonomous Region, on July 6, 2012. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Horses graze at the Hulun Buir grassland, north China's Inner Mongolia Autonomous Region, on July 6, 2012. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

Photo taken on July 7, 2012 shows Hulun Buir grassland in north China's Inner Mongolia Autonomous Region. The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer. (Xinhua/Zhao Tingting)

The beautiful scenery of the vast grassland, forests, rivers and lakes, as well as the unique customs of the Mongolian ethnic group, have attracted a great number of tourists at home and abroad to Hulun Buir grassland every summer.