It can grow higher than the leaning Tower of Pisa and is the tallest living structure in our oceans

Kelp forests are rich underwater ecosystems found along coastlines worldwide, providing habitat and food for diverse marine life.

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Giant kelp (Macrocystis pyrifera) can grow up to 60m tall and as fast as 60cm per day. To compare, the Leaning Tower of Pisa measures 58.36 metres (191 feet) on its highest side.

California’s kelp forests are among the most significant – and magnificent – in the world, supporting species such as sea otters, leopard sharks, Garibaldi fish and harbour seals.

Drop beneath the waves with this tranquil video filmed off the coast of California.

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Main image: Kelp forest. Credit: BBC Natural History/Getty