The landscapes of the Near East show both the first settlements and the longest trajectories of settlement systems. Mounding is a characteristic property of these settlement sites, resulting from millennia of continuing settlement activity at distinguished places. So far, however, this defining feature of ancient settlements has not received much attention, or even been the subject of systematic evaluation. We propose a remote sensing approach for comprehensively mapping the pattern of human settlement at large scale and establish the largest archaeological record for a landscape in Mesopotamia, mapping about 14,000 settlement sites-spanning eight millennia-at 15-m resolution in a 23,000-km 2 area in northeastern Syria. To map both low-and high-mounded places-the latter of which are often referred to as "tells"-we develop a strategy for detecting anthrosols in time series of multispectral satellite images and measure the volume of settlement sites in a digital elevation model. Using this volume as a proxy to continued occupation, we find a dependency of the long-term attractiveness of a site on local water availability, but also a strong relation to the relevance within a basin-wide exchange network that we can infer from our record and third millennium B.C. intersite routes visible on the ground until recent times. We believe it is possible to establish a nearly comprehensive map of human settlements in the fluvial plains of northern Mesopotamia and beyond, and site volume may be a key quantity to uncover long-term trends in human settlement activity from such a record.A ssessment of the scale and spatial distribution of human communities in past societies has been a key objective for archaeological research over the last 50 y (1), especially in the Near East, where questions of the origins of urbanism, the state, and empires are almost always approached via a regional perspective (2), and most commonly using the methods of archaeological survey. The pioneering surveys of the 20th century focused on the top of the settlement hierarchy, in the form of the largest mounds (e.g., refs. 3 and 4), but it is now appreciated that by overlooking smaller sites such an approach can produce misleading portraits of settlement systems, particularly those of nonurbanized phases (5). The challenge for archaeologists is to maintain coverage extensive enough to discern significant spatial patterning while increasing survey intensity in order to locate these smaller sites. The first generation of survey archaeologists opted for the former half of this classic tradeoff; more recent generations have increasingly adopted the latter intensive approach.Many surveys have met this challenge by employing various remote sensing datasets. Of the three primary physical properties characterizing sedentary Near Eastern sites since the Neolithicdense surface artifact assemblage, moundedness, and anthropogenic sediments-the latter two can be detected in aerial or satellite imagery and can potentially be recorded at large scale. Indeed, nearly a...