Are you on a charter boat or using the ferry? If on a boat, I love the various anchorages in the national park areas on St. John - Trunk, Cinnamon, Maho, Francis bays. There's nothing ashore, unlike the anchorages in the BVI. Keep in mind that when sailing into the USVI, all non-citizens or non-LPRs must have a visa; there's no ESTA when travelling on a sailboat. If you are only in the USVI for a couple of days, then St. John will have everything you need. For a longer stay you can continue onwards to St. Thomas.