Five-level stack interchange in Tampa, Florida
The interchange opened in 2014, along with a tolled elevated causeway bridge that connects the two highways. The causeway bridge is of extremely similar design to that of the elevated express lanes along FL-618 Toll.
The elevated express lanes are part of the reason for the unusual design of the interchange. A traditional five-level stack has five flyover ramps directly stacked on top of each other. The Selmon Expressway Interchange has five levels of flyover ramps, but they are not all directly stacked - rather some of them are off to the side of the others, etc. The interchange contains ramps between the general purpose lanes of FL-618 Toll, the express lanes of FL-618 Toll, the elevated causeway bridge, and the ramps between I-4 in both directions and the causeway bridge.
An all-electronic SunPass or “Pay-by-Plate” toll gantry is located on the elevated causeway bridge, about 1,500 feet from the interchange.