The current cable-stayed bridge opened in 1987 to replace a previous twin-span cantilevered through truss bridge. One of the cantilever spans collapsed and the other was damaged when a freighter struck one of the main structural piers in 1980, thus putting the bridge out of service. The bridges had been struck by ships previously, so were already not at their strongest.
In the seven years between the collapse and damaging of the original bridges and the construction and opening of the new bridge, a ferry was operated across the mouth of Tampa Bay, but saw very little use due to the long wait times and the long operation times. Many motorists chose to take Interstate 75 north around Tampa Bay, and then cross onto the St. Petersburg peninsula via either the Howard Frankland Memorial Bridge or the Gandy Bridge.
The cable-stayed replacement Sunshine Skyway features five large manmade islands in front and behind the main structural piers, known as “Dolphins”. These are designed to absorb the impact of a crashing ship to prevent a collapse from happening again, since the Skyway is a vital transportation link for Greater Tampa.
The bridge structure is just over 4 miles long. The approach highway on either side is approximately 7 miles between toll plazas, and the cable-stayed main span is 1,200 feet long.
The approaches from the original span that was damaged but did not collapse were salvaged on both ends of the bay, and are now used as fishing piers that often some spectacular views of the bay and the Skyway.
OK, slight correction to my last comment. As I stated before, it connects Pinellas and Manatee Counties, but it does go across an extremely small portion of Hillsborough County, which is all water and the main shipping channel under the bridge.
This bridge is not in Hillsborough County. It connects Pinellas County and Manatee County.