The Loobu is a river in northern Estonia. Its source is about 12 km southwest of Rakvere in Lääne-Viru County and it drains into Eru Bay (part of Finnish Gulf) near the village of Vihasoo in Lahemaa National Park.

Its drainage basin is rather small and narrow. The Loobu lacks any major tributaries.

At Joaveski, 10 km upstream from its mouth, the Loobu flows over the Baltic Klint, forming Joaveski Falls.

Kadrina (population: 2,600) is the only significant settlement on the river.

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  Undla, an impounded lake on the Loobu
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  A fish ladder on the Loobu
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  Joaveski Falls

• "Technical assistance for improvement of ecological quality of watercourses" (PDF) (in Estonian). Retrieved 2008-11-14.

59°34′14″N 25°47′49″E / 59.57056°N 25.79694°E / 59.57056; 25.79694