Gesher Benot Ya'aqov, located in the Dead Sea Rift valley, is one of the oldest non-African sites to have yielded evidence for the activities of groups of hominin hunter-gatherers. The excavations recovered thousands of Acheulian period stone tools and animal bones that had accumulated in and around an ancient lake about 780, 000 years ago. The deposits have remained waterlogged virtually ever since, and this unusual circumstance resulted in the preservation of plant macrofossils, including pieces of wood and bark that can be identified to the level of individual plant species. Most of the pieces probably accumulated naturally around the lake, but a few show signs of hominin modification - making them the oldest wooden artefacts yet discovered. The unique contribution of the Gesher Benot Ya'aqov palaeobotanical assemblage, however, lies in its value for the palaeoenvironmental reconstruction of a pre-agricultural age - an age that predates changes induced by intensive human activity. This monograph describes the geological and archaeological context of the ancient wood, the criteria for its identification, and its implications for the woods surrounding Gesher Benot Ya'aqov in Lower to Middle Pleistocene times. They include detailed descriptions of the different wood taxa, discuss the present habitats of the identified species, and consider the possible mechanisms by which the wood was deposited. They also provide a survey of the wood fragments that have occasionally been found at other ancient Palaeolithic sites. This volume is the first in a series of monographs which will focus on different aspects of the multidisciplinary investigations at Gesher Benot Ya'aqov.