Trunk Bay is a Beach-side Bay so you walk to the beach from the parking lot where the jitney parks. For non-snorkelers, they will have a beautiful beach to sun or play on. There is a small island about 100 feet off the shore and the snorkeling trail is to one side of it. You can wade out to the snorkeling area until the water is deep enought to swim or snorkel. Where the coral and fish life are located around the island is about 6 to 10 or so feet deep. To see them up close you have to dive down to just above the coral. You don't want to touch the coral as they are "protected" in this environment. It is easy enough though, to dive down, see the coral and fish and come up for air or just cruise along the surface with the snorkel and enjoy the view. The water is a rich tourquois color. You'll love it.
The boat had about 60 of us snorkelers and was not full. It could hold about 150 people. It had air conditioning inside on the main deck or you could enjoy the upper deck in the open air where most of the passengers enjoyed the trip. The excursion leader described the coast line and pointed out the island vacation homes of famous people as we went by such as Michael Jordan's home.
The whole trip was fun and we returned to the ship in time to get the last lunch serving. Trunk Bay is said to be one of the 10 best beaches in the world You will enjoy it.