What is that?

If you know, let us know. Send your responses to [email protected] or phone (631) 749-1000, extension 354.

Mallory Samson and Ellie Pedone were the early birds, emailing us that last week’s photo (see below) is of the Shelter Island Heights Beach Club.

Tom Speeches also emailed with the correct answer and Cynthia Michalak weighed in on Facebook.

Bill Dooley wrote that he remembers “back in the 30s and 40s, as you entered on the right, there was a large stone with a metal plaque, and on the left was a novelty shop selling ice cream, candy and beach toys for kids under the management of Tom Gilbride. At that time it was a two-story pavilion associated with the Prospect Hotel. Fond memories.”

Charity Robey, in a story on the club last year, wrote: “In the beginning, it was the Prospect House Bathing Pavilion, built around the same time as the Prospect House in 1872.

“Prohibition led to the creation of a two-story beach club in 1907 with an open porch on the second floor designated as the Sihaqua Club, since private clubs could sell alcohol legally.

“The Heights community has always been a self-contained area on the Island, maintaining its own designated facilities. Amenities such as a pavilion reinforced a close-knit sense of kinship for its population. People would come to the beach to swim, eat, hear music and watch the sunset, much like today.”