The mouth of the Indian River, which flows into the ocean at Portsmouth, was once a Carib Indian settlement. A rowboat ride down this river, which was featured in Pirates of the Caribbean: Dead Man's Chest, is both relaxing and educational. The river is lined with trees whose buttress roots spread up to 20 feet. Clear, brackish water is a playground for young barracudas and crayfish. Except for singing yellow warblers, flitting hummingbird or wing-flapping egrets, there is an eerie silence. To arrange such a trip, stop by the visitor center in Portsmouth and ask for one of the "Indian River boys," of the Portsmouth Indian River Tour Guides Association. Most boat trips take you up as far as Rahjah's Jungle Bar. You can usually do an optional guided walking tour of the swamplands and the remnants of one of Dominica's oldest plantations. Tours last one to three hours, for roughly $20–40 per person, but the actual price depends on your guide.