Oahu is the third-largest island in the Hawaiian archipelago and is known for its diverse landscapes, including beautiful beaches, lush mountains, and vibrant urban areas. The capital city, Honolulu, is located on Oahu and serves as the main hub for tourism, culture, and commerce in Hawaii. The island is famous for its historical sites, such as Pearl Harbor, and popular tourist destinations like Waikiki Beach. Oahu also offers a variety of outdoor activities, including hiking, surfing, and snorkeling, making it a popular choice for visitors seeking both adventure and relaxation.