The most popular hike on St. John  is the 2.1-mile Reef Bay Trail, which descends from Centerline Road to the shore at Reef Bay . The trail passes through both moist and dry tropical forests and the remains of four different sugar factories, including the extensive Reef Bay ruins. The hike descends 600 feet from start to finish. Plan on two hours to hike down, three to hike up.
Several markers along the way identify significant plants, trees, and landmarks. You may see white-tailed deer along the trail. Introduced on St. Thomas and St. John as game for planters, the deer swam to St. John and have flourished. They are not fearful of people.
The 0.25-mile spur trail to the Reef Bay Petroglyphs  branches off 1.6 miles down. Just past the petroglyph trail is the beginning of the Lameshur Bay Trail. It’s a 1.5-mile hike to that bay. The Reef Bay Great House Ruins are a short distance up this trail. If you keep going straight, you come to the Reef Bay Sugar Ruins and a short spur trail to Little Reef Bay, where you can swim.
The National Park Service leads guided hikes down the Reef Bay Trail several days a week. On these hikes a ranger leads about 30 people down the trail, stopping regularly to describe the natural and historic landmarks along the way. This is a great opportunity to learn about the island, but the biggest perk of the outing is that you don’t have to hike back up.
The Park Service arranges a boat to pick you up at the end of the trail and sail back to Cruz Bay . The hike costs $20 per person. Sign up early, preferably before you arrive on St. John , because it is almost always fully subscribed.