The book consists of three sections of contributions representing novel ideas focusing on the quantity, quality, and actual condition of the monumental built environment of the ancient Maya in the northeast of the department of Petén, Guatemala. A special catalogue is its major contribution. It includes detailed, systematic and updated descriptions for comparative purposes. 64 archaeological sites are described in the form of technical data sheets, some of which are reported for the first time. In addition to the descriptions, the sites are illustrated by plans, isometric views, and several by photographs. Further chapters deal with an analysis of urban space and cover aspects of conservation, presentation and use of the built environment as part of the National Heritage. Consolidated and restored ancient Maya cities ready to attract visitors are important landmarks for the future of the archaeological heritage of the north eastern Petén.