One of the three great rivers of Siberia, emptying into the Arctic through a 1,000 km-long bay.
Length
3,650 km
Source
Altai Mountains
Mouth
Arctic Ocean (Gulf of Ob)
Continent
Asia
Countries
Russia
Did you know?
With its tributary the Irtysh, the Ob is one of the longest river systems in the world.
Little-known fact
Because it flows north, its upper reaches thaw while the mouth is still frozen — causing enormous spring floods across Siberia.
Highlights
- A great Siberian river
- Among the world's longest systems
- Causes vast northern spring floods
Life in the Ob
The fish and animals, waterbirds and water plants — including some of the rarest — that this water supports.
Animals & fish
Northern pike
A long, torpedo-shaped ambush predator that lurks among weeds across the cool rivers and lakes of the north.
Eurasian otter
A sleek, playful hunter whose return to a river is a sign the water has run clean again.
Waterbirds
Mallard
The familiar green-headed dabbling duck — ancestor of most domestic ducks — found on waters worldwide.
Interactive · 3D journey
Journey of a river · source → sea
Every river runs the same great journey — from an icy mountain spring, down through gorges and looping meanders, to a wide delta where it meets the sea. Tap a stage to follow the water downstream.
Tip: hover to tilt the valley · tap a stage to float downstream
The Source
Every river begins high up — in a mountain spring, a melting glacier or a boggy upland. The water is cold, clear and fast, tumbling down the steepest ground of its whole journey.
Landforms here