Tintagel (symphonic poem) - Arnold Bax

Tintagel is a symphonic poem by Arnold Bax. It is his best-known work, and was for some years the only piece by which the composer was known to many concert-goers. The work was inspired by a visit Bax made to Tintagel Castle in Cornwall in 1917, and, although not explicitly programmatic, draws on the history and mythology associated with the castle.

--quoted from the Wikipedia article on Bax's Tintagel

For more of his work, check out Wikipedia's list of compositions by Arnold Bax. I myself am partial to his tone poems, though his symphonies are also excellent.