Seven Mile Beach, the barrier island on which Avalon and Stone Harbor were established,was purchased by Aaron Leaming in 1723.Access to the  island was only by boat.Leaming used yhe island for grazing cattle  in the summer and for  hunting.Extensive Marshes Seperated the island from the island from the mainland and covered much of it .Avalon has one of the only remaining high dune systems on the east coast.Two species of endangered nesting birds, Piping Plovers and Least Terns, visit Avalon each summer to nest in the sand, between 8th - 23rd Streets and 43rd - 60th Streets. Certain areas will be posted as nesting begins and access will be prohibited. During the nesting season, beach raking will be coordinated to avoid destruction of nests. Some areas of wrack line (high tide "grassy" line) may be left to provide a feeding area for chicks. A brochure about these birds is available at Community Hall.Seven Mile Beach Company Headed by Philadelphian Frank Sidal, Purchased  three thousand acres of fast land  in 1887,with the objective of  founding a resort colony .For the first  few years colonist had to collect rain waterfor drinking and cooking.