Photo of the Day

July 3, 2017

Underground Exploration

An explorer treks through the Tú Làn caves in Vietnam. The vast underground system is composed of at least 10 known caves. It is believed the whole cave network has yet to be fully explored. A previous version of this caption incorrectly identified the cave pictured as the Sơn Đoòng Cave. The caption has been corrected to identify the Tú Làn caves. This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at for the latest submissions and news about the community.
Photograph by Denys Kutsevalov, National Geographic Your Shot

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