A draw (US) or re-entrant (international), is a terrain feature formed by two parallel ridges or spurs with low ground in between them. The area of low ground itself is the draw, and it is defined by the spurs surrounding it. Draws are similar to valleys on a smaller scale; however, while valleys are by nature parallel to a ridgeline, a draw is perpendicular to the ridge, and rises with the surrounding ground, disappearing up-slope. A draw is usually etched in a hillside by water flow, is usually dry, but many contain an ephemeral stream or loose rocks from eroded rockfall.