Photo taken by Jan from China Tibet Online shows two foreign runners who take part in 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows an experienced referee directing staff members before 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows a 13-year-old boy who takes part in 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows a 77-year-old runner from inland China who takes part in 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows an aged participant running on the way during 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows some young participants enjoying running during 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

 Photo taken by Jan from China Tibet Online shows two foreign runners waving their hands during 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.

Photo taken by Jan from China Tibet Online shows two runners trying to catch up with each other during 2010 Fifth International Half Marathon Challenge held in Lhasa, Sept. 12.