Cambodia was once home to the powerful Khmer Empire, which ruled much of Southeast Asia from the 9th to 15th centuries. The Khmer built hundreds of massive temples at their capital of Angkor Thom, including Angkor Wat, considered the largest religious structure in the world. Over time, the Khmer kingdom declined as the jungle overtook the abandoned temples. The site was rediscovered in the 19th century and restoration efforts continue today to reclaim the temples from the encroaching forest. Visitors can now see the ongoing struggle between nature and architecture at temples like Ta Prohm, where trees grow from the walls and their roots split the stone.