Sid the Sediment begins his journey in the mountains as rain and melting snow cause cracks in rocks over time. As the cracks widen, Sid falls off and is carried by flowing water forming small channels that join larger streams and rivers. On his long journey, Sid rubs against other rocks, smoothing his edges and getting smaller as the flowing water cuts away land and forms valleys, carrying sediments away until Sid's journey ends with him deposited as a small grain on a beach.