The map area, in east-central Vermont and adjacent New Hampshire, consists of parts of the Lower Waterford, Concord, Littleton and Miles Pond 7 1/2-minute quadrangles (Fig. 1) that together constitute the Littleton 15-minute quadrangle. The mapping is part of the effort to produce a new bedrock geologic map of Vermont through the collection of field data at a scale of 1:24,000. The focus of my part of the project is to map and interpret the "New Hampshire sequence" rocks (White and Jahns, 1950) that crop out in Vermont and their relationship to those of the "Vermont sequence", or the Connecticut Valley trough, west of the Monroe line, here a fault (Hatch, 1988a). The work is a continuation of mapping just initiated by N.L. Hatch, Jr., prior to his death in 1991. This particular map area was chosen as the place to initiate this study because it includes one of the largest areas of the New Hampshire sequence in Vermont, because it is adjacent to and on strike with the Littleton-Moosilauke area in New Hampshire that includes the type area of most of the units of the New Hampshire sequence (Billings, 1935, 1937), and because the Connecticut River here runs roughly east to west across the regional strike and might provide a good stratigraphic section across the rocks under study. The mapping showed that no bedrock is exposed along either bank of the Connecticut River across most of the area, but there are excellent exposures in the spillways of two large dams, Moore Dam on the east and Comerford Dam on the west (about 100 m west of the Lower Waterford quadrangle), along Interstate Highway 93 (1-93), and adequate exposures in the hills above the river. My mapping was mostly in the Vermont parts of the Littleton 15-minute quadrangle but included some work in the Barnett 7 1/2 x 15-minute quadrangle to the west and a zone along the New Hampshire side of the Connecticut River that included Albee Hill, Partridge Lake, Highland Croft farm, the former Fitch farm, and the outskirts of Littleton. The Vermont mapping is thus tied to the classic Littleton-Moosilauke area of Billings (1937) and the fossiliferous Fitch and Littleton Formations in their type areas.