The southern Chinese province of Hainan is studying a feasibility report on the possibility of building a bridge or tunnel across the Qiongzhou Straits. Some US$2.4 million has been allocated for preliminary research. The 22.5km-wide Qiongzhou Straits separates Hainan Island and Guangdong province and the bridge or tunnel would be 31km long. A railway across the straits opened two years ago.