Not only is it possible to get to Mary Boon from BSV, that's just the beginning of a Simpson Bay walk. It is our absolutely favorite thing to do while we're on island, and do it numerous times each visit. We now park at Dinghy's Beach Bar, have a drink and tell them we'll be back for lunch, later after our walk. You can walk the beach all the way to The Secret Seafood House, at which point you run out of beach, but there is a wooden ramp up to the restaurant (slippery when wet) and have a drink before your walk back. It's quite the walk, but this beach has firm sand or soft sand if you prefer, all the way from start to finish. It's a huge beach, but somehow you feel as if you're all alone on your walk. For some reason after a 3 hour walk on Simpson Bay I feel like I'm a happier person.