text:  As is often the case with huge ancient ruins , knowledge of the site was never completely lost in the region . It seems that local people never <unk> about <unk> and they guided <unk> expeditions to the ruins in the 1850s . Some second- or third @-@ hand accounts of <unk> appeared in print starting in the 17th century , continuing through the writings of John Lloyd Stephens in the early 19th century ( Stephens and his illustrator Frederick <unk> heard rumors of a lost city , with white building tops towering above the jungle , during their 1839 @-@ 40 travels in the region ) . Because of the site 's <unk> from modern towns , however , no explorers visited <unk> until <unk> <unk> and <unk> <unk> , respectively the commissioner and the governor of <unk> , visited it in 1848 . Artist <unk> <unk> accompanied them and their account was published in Germany in 1853 . Several other expeditions came to further investigate , map , and photograph <unk> in the 19th century ( including Alfred P. <unk> in 1881 @-@ 82 ) and the early 20th century . <unk> archaeologists started to clear , map and record the ruins in the 1880s . 
  