Ice rides over the upstream side and smoothes off the outcrop, but pulls blocks away from the downstream side, creating a blocky, steep front. Thus the ice flow here was from right to left. This one in central Washington is especially impressive. The city of Madison, Wisconsin lies between several glacial kettle lakes. The lakes formed when glacial ice remained behind in a former river valley and was buried by outwash deposits.
Water diverted by ice is termed ice-marginal drainage .
In the foreground is the edge of a moraine in northeasternmost South Dakota. In the distance are several dark strips which mark valleys cut by streams flowing along the ice margin. The most distant one is the Missouri River, which is essentially an ice-marginal drainage along the lower half of its course. Subtle braided textures can be seen on these fields in Ohio, marking the locations of former braided glacial meltwater streams. The potholes are believed to have formed when melt water from the glaciers flowed down the bluffs here.