Once home to the Lido Beach Casino, Lido Key‘s reputation for marrying cosmopolitan life with seaside paradise continues today. Catch some rays or take a walk on the shore and put your toes in the soft, white sand of Lido Beach. Within a short radius lies St. Armands Circle, a sophisticated outdoor dining and shopping area with distinct European flair, iconic examples of mid-century modern architecture and the turquoise waters of the Gulf of Mexico.