Phong Nha-Kẻ Bàng is a UNESCO World Heritage Site located in Quang Binh Province, Vietnam. It is renowned for its stunning limestone karst landscapes and extensive cave systems, including the famous Phong Nha Cave and Son Doong Cave, which is the largest cave in the world. The area is rich in biodiversity, hosting numerous species of flora and fauna. The park covers approximately 885 square kilometers and features a variety of ecosystems, from tropical forests to rivers. It is a popular destination for adventure tourism, offering activities such as cave exploration, trekking, and river kayaking, attracting visitors from around the globe.