In this landmark series for BBC1 Wales, filmed in ultra high definition (UHD) we dive into the natural wonders of the Welsh seas. The series features some of the largest creatures of the deep ocean, birds that can ‘fly’ underwater, and the tiniest marine life with the biggest personalities. In four beautifully-crafted episodes we join the animals that live their lives on the edge in Coasts; jump into the mythical kingdom in the Shallow Seas; and head into the unknown for The Deep. In the final episode we look at the environmental challenges facing the marine environment as we meet the Heroes of the Celtic Deep. Narrated and presented by Dame Siân Phillips, with music by Paul Mellor performed by the National Orchestra and Chorus of Wales.

Starts Tuesday 12th October 2021, 21:00, BBC One Wales with episodes following every Tuesday for the next 4 weeks.

All four episodes are now available to stream on BBC iPlayer:

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Meet the talented team behind the making of our natural history debut …

View the tribe

View behind the scenes!

Coming soon

Who doesn’t like an aquatic selfie?

Coming soon

We’re very excited to announce the publishing of the Wonders of the Celtic Deep book by Graffeg. Available to purchase via their website below:

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We have an extensive range of landscape and natural history footage for sale filmed across the UK, particularly a huge selection from Wales.

Archive for sale


View the taster for Wonders Of The Celtic Deep!

The official trailer is out now!

Watch the behind the scenes of EP 1

Coasts: Life on the Edge

Seal Pups

Flirty Seals

Prawns vs Blenny

Shallow Seas: A Mythical Kingdom

Crab Fighting

Catfish lays eggs

Sea Kayaking in Pembrokeshire

The Deep: Into the Unknown

Basking Sharks


Diving Dolphins

Heroes of the Celtic Deep 


Seal Rescue

Cleaning the coasts

With thanks to …