Although over 20% of the City of Buffalo is water, there are few actual beaches in the city limits. Times Beach existed until the early 20th century, and today it has reverted to a marshy nature preserve.
The small beaches that exist within city limits are the beach at Wilkeson Point, and Gallagher Beach, both just across from downtown on the Outer Harbor:
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bpawlik, on Flickr
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bpawlik, on Flickr
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bpawlik, on Flickr
The closest popular swimming beaches just outside the city limits are Beaver Island, Woodlawn Beach, Crystal Beach, and Sherkston Beach.
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Beth Hyzy, on Flickr
Woodlawn Beach by
tribe7, on Flickr
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melissa, on Flickr