Originally a continuous state road extending from Bonita Springs to Tice by way of Fort Myers Beach and Fort Myers, SR 865 now consists of two segments connected by a part of CR 865, which also extends to the north and south of the state segments.

The historic southern terminus of SR 865 is an interchange between Interstate 75 (I-75 or SR 93) and Bonita Beach Road in Bonita Springs, though the current county designation actually begins 2.2 miles (3.54 km) east of the interchange near Logan Boulevard.

State maintenance begins the intersection of Estero and San Carlos boulevards just east of Bodwitch Point Park.

The southern section of SR 865 continues northward its northern terminus, an intersection with McGregor Boulevard, which is SR 867 to the northeast of the intersection, and CR 867 to the southwest, a more direct route connecting downtown Fort Myers to the popular Sanibel and Captiva islands.

At this point, SR 865 ends and CR 865 resumes, proceeding east along Gladiolus Drive.

It begins at Tamiami Trail (US 41) and terminates at an intersection with Metro and Michael G. Rippe Parkways (SR 739).

This portion of the parkway historically served as the first mile of the Seaboard Air Line Railroad's Punta Rassa Branch.

Beyond the northern section's terminus at SR 739, historic SR 865 continues along Six Mile Cypress Parkway and turns north passing the Lee County Sports Complex, which contains Hammond Stadium, the spring training home of the Minnesota Twins major league baseball team.

Parts of Ortiz Avenue were originally signed State Road 80B before being connected to the rest of SR 865.

[21] The entire route from Bonita Springs to Tice would only be designated SR 865 for a short time before the state relinquished portions to the county.