Sunset Beach is a residential beachfront community and beach located at the southern tip of Treasure Island, Florida in Pinellas County. One of three main Treasure Island beaches, along with Sunshine and Mid-Island, it is primarily a residential beach neighborhood. Mid-century fisherman cottages mix with lush Key West-style homes, between the Gulf of M…Sunset Beach is a residential beachfront community and beach located at the southern tip of Treasure Island, Florida in Pinellas County. One of three main Treasure Island beaches, along with Sunshine and Mid-Island, it is primarily a residential beach neighborhood. Mid-century fisherman cottages mix with lush Key West-style homes, between the Gulf of Mexico and Boca Ciega Bay. From the southern end of Sunset Beach, one can look directly across Blind Pass at Upham Beach in St. Pete Beach.