Bannerman Island, located in the Hudson River, is home to the ruins of a historic military surplus warehouse built by Francis Bannerman VI in the early 1900s. The island, part of the Hudson Highlands State Park, is known for its picturesque views and unique architecture, which includes a castle-like structure. Today, Bannerman Island is a popular destination for visitors interested in history and nature. The island is accessible by boat, and guided tours are offered to explore its remnants and learn about its past. It is also a habitat for various wildlife, making it a serene spot for nature enthusiasts.