Volume 1 of The Caves of Thailand covers the eastern and north-eastern provinces of Amnat Charoen, Bueng Kan, Buriram, Chachoengsao, Chaiyaphum, Chanthaburi, Chonburi, Kalasin, Khon Kaen, Loei, Mahasarakham, Mukdahan, Nakhon Nayok, Nakhon Phanom, Nakhon Ratchasima, Nong Bua LamPhu, Nong Khai, Prachinburi, Rayong, Roi Et, Sa Kaeo, Sakon Nakhon, Sisaket, Surin, Trat, Ubon Ratchathani, Udon Thani and Yasothon. Over 1, 100 caves, rock shelters, stream sinks, resurgences and other sites of speleological interest are fully detailed, supported by 78 surveys and a bibliography with over 200 references.