Dozens of firefighters fought to tackle the blaze which took hold of the partly wooden pier in the North Somerset seaside resort at about 0700 BST.
No-one was injured in the fire, which firefighters said started in an area containing deep fat fryers. Black smoke was visible more than 10 miles away.
The owners, who have recently bought and refurbished the pier, were said to be "absolutely devastated".
... Dee Williams, deputy manager of the Grand Atlantic Hotel, which lies 200 yards from the pier, described the fire as "an inferno" and heard loud bangs which she believed to be fireworks left over from a recent display.
"It is part of our identity and would really affect trade if we were to lose it," she said.
Jacquie Whelan, owner of Sunfold Hotel on Beach Road, said it was a "horrendous" sight, with massive red flames, hundreds of feet in the air, all over the pier.
It first opened in 1904 and was later bought by the Brenner family who sold it earlier this year in a multi-million pound deal to brother and sister Michelle and Kerry Michael.'
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