The river is joined by a tributary from the north at South Ashfield (69.9), and the streams occupy deep but open valleys. Kame terraces flank the rivers and are a source of gravel for road ballast. The old dam (73.9) near Conway is a picturesque spot, and the deep, shady pool below is not neglected by anglers. Glacial erratics (see pp. 8-9) dot the hill slopes, but ledges are rare and consist of the locally named Conway schist where the rock does appear at the surface. The road branches again at Conway: the left fork goes north along the dissected brink of the Deerfield gorge to Shelburne Falls, but our choice falls upon the eastward route to South Deerfield. The highway climbs through a cut (75.8) in contorted, gneissic Conway schist, which seems to be lined with twisted white quartz veins from this point to the margin of the Connecticut Valley. The road levels off just before it reaches the New England upland, and then it drops through rolling hill country to the shaded valley of Mill Brook (77.4), which it follows to the edge of the lowland (80.1). Rocky ledges are common along this swiftly flowing stream. A good view of the Pocumtuck Hills appears on the left (79.7), with the flat plain of the old Deerfield delta stretching to their base. The road crosses this plain and enters South Deerfield (81.8). The tour turns north on Federal Highway 5, which is built on the deposits spread in glacial Lake Hadley by the Deerfield River from its mouth eastward to the foot of the Pocumtuck Hills of Triassic conglomerate. Bloody Brook (82.2) drains this part of the plain. North of the road which goes through the notch between the Sugarloafs (82.6), the delta deposits continue as a terrace along the base of the Pocumtuck Hills as far as Cheapside. But the Deerfield has excavated its post-glacial delta, and the roadway descends to the meander-cut floodplain (84.4 to 88.1), though it rises over one of the meander scarps (85.1). Remnants of the Deerfield delta form a terrace due west across the valley and on the margin of the hills. The entire lowland north of the meander-cut terrace was inundated in 1936, and the water level may still be identified by debris on the railroad embankment on the right. Old Deerfield (86.1) itself is on a meander-scarp terrace, and the 1936 flood line is well marked along it. After the road crosses the Deerfield River (88.3), it leaves the floodplain as it climbs to the center of Greenfield (89.8). _Greenfield, Orange, Pelham, Amherst, and Deerfield_