Sunshine Skyway Bridge, Tampa
I love the Courtney Campbell...route 60 across the bay from Tampa towards Clearwater. There are many parking areas where you can stop and walk on sand (not the beach, but sand beside water nonetheless). It is even a great view if you're just driving across...many minutes of water at eye level on both sides.
The I275 bridge over the bay, Tampa towards St Pete, goes way up in the air, so you're not next to the water. However, if you're traveling east, you get a great view of the city skyline.
The Skyway is definitely worth the trip....it really seems like you're driving up to the sky. Maybe even a little creepy. Go at night to see the bridge when the suspension wires are lit. They look like they're glowing. Also great to go across at sunset...but don't get too distracted by the sky! Also, beside the Skyway, the old bridge is preserved as piers on either end of the Skyway. Several years back...maybe 10-15 years, a ship ran into the bridge and destroyed it, and therefore the Skyway was built. It costs a couple of dollars to drive on the pier.