To give a little more info...we have a condo 5 minutes away from Honeymoon Island, and we're at the park probably 5 nights a week watching sunsets on the Gulf. Caladesi and Honeymoon Island are both part of the State Park system. Before you spend the money (and time) to go over to Caladesi, I suggest you go to check out the Main Beach at Honeymoon Island first. There is a large pavillion at the main beach...gift shop, full service snack bar, His & Hers restrooms/changing rooms with showers, and decks w/picnic tables that can be used by people who purchased food or beverages at the snack bar...beer & wine are available but must be consumed on the deck...no alcohol allowed on the State Park beaches. Contrary to what has been reported, the swimming beach at Honeymoon Island is quite large (the main beach) and is mostly very soft sugar-sand. The auxiallary beaches on Honeymoon Island are rockier/more shells, but the main beach is fine sand. There are several beaches on Honeymoon Island, but the Main Beach is best for swimming. They rent beach umbrellas. You can also rent bikes. There is an excellent trail system throughout the park, as well as a Nature Center. There are 3 buildings with restroom/changing facilities on Honeymoon Island, and 2 of them have snack bars. (the middle one is the Main Swimming beach, the eastern one also has snack bar, and is near the dog beach, and the far one is on "Oasis Beach" which is also a softer-sand beach but a bit more rocks/shells and not as large as the Main Beach.) During slow times of the year, only the Main snack bar is open but in the summer they both are.
The ferry is $2 per person, and is not always available (for instance, on windy days they will not run the ferry, or days with strong undertow in Hurricane Pass...the water that separate Honeymoon Island from Caladesi.)
There are no life guards at any of the beaches there...Clearwater Beach has lifeguards, but not the STate Parks.
The shelling on Honeymoon Island is best at the far end of the island...drive past the turns for Oasis beach parking, and go to the North lot. You don't have to "hunt" for shells there, just scoop 'em up. There are a kazillion shells there...at low tide you can even find small conch shells