Tourists visit the Shanghai Zoo during the Tomb-sweeping Day holiday, April 4, 2017. [Photo/VCG]

BEIJING - China's tourism industry raked in 39 billion yuan ($5.74 billion) in revenue during the Tomb-sweeping Day holiday, official data showed on Tuesday.

The revenue was driven by 93 million domestic tourist trips, the National Tourism Administration said in a statement.

Tomb-sweeping Day, also known as Qingming Festival, is an important occasion for Chinese to honor their ancestors. Many also spend the three-day holiday on leisure travel.

Most of the tourists hit the road for short-haul trips. Meanwhile, railway operator sent 35 million passengers, most of whom headed for the Beijing-Tianjin-Hebei area and the Yangtze River Delta region.

China's tourism industry is key to the country's shift towards a more service-driven economy and is a useful indicator of the strength of consumer spending.