Sutton Hoo Treasure
Sutton Hoo Helmet
The replica helmet and mask are part of the Sutton Hoo Treasure (Wiki) with more at Sutton Hoo Site. The original find is further down together with more artifacts from antiquity.
The British Museum (for details, admission and location) is probably the largest in the UK and contains artifacts from all over the world, from antiquity to more recent times. Whilst there is some controversy about ownership of some items (e.g. the Elgin Marbles), the museum has preserved what otherwise might have been lost and is free to all visitors. There is a an extensive cloakroom and non-commercial photography is allowed.
Of similar interest is the Victoria and Albert Museum, which is dedicated to design from across the world. More from the British Museum:-
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