A river changes shape as it flows from its source to its mouth. The shape of both the long profile (a slice through the river from source to mouth) and the cross profile (a slice across the river) changes.

Upper Course:

• e.g. Catshaw Greave, River Wyre
• 1.5km wide valley
• 150m high valley
• 400m above sea level 

• Vertical erosion
• Boulders, cobbles and pebbles deposited, 
• V-shaped valley (no flood plain)
• Low sinuosity 
• Waterfalls (e.g. High Force, River Tees) 
• Plunge pools
• Gorges
• Headward erosion
• Potholes
• Many tributaries

Middle Course

• e.g. Marshaw Wyre

• Lateral erosion
• Pebbles, gravel and some sand deposited
• Small flood plain
• Higher sinuosity

Lower Course

• e.g. Great Eccleston
• 5km wide valley
• 20m high valley
• 4m above sea level

• Lateral erosion
• Sand, silt and clay deposited
• Large flood plain
• High sinuosity
• Levees
• Oxbow lakes (and meander scars)
• Braided channels
• Delta (at river mouth)