Abstract: Heybeli travertines and tufas crop out in the north of Lake Van, in the region between Heybeli village and Lake Van. While there is a 55 m travertine sequence at the base, a 21 m thick tufa sequence lies above these travertines. As a result of field and laboratory studies, Heybeli travertines and tufas were divided in 8 facies: brecciated-lithoclastic facies, crystalline crust facies, scrub type facies, raft type facies, gas cavity facies, phytoherm roofstone facies, phytoherm boundstone facies and micritic tufa facies. The data obtained in the study indicate that tectonism, volcanism and lake level changes played an active role in the formation and development of these travertines and tufas.