High Quality Content by WIKIPEDIA articles! The Kopu Bridge (originally Hauraki Bridge and sometimes Waihou River Bridge) is a single-lane swing bridge that spans the Waihou River, near its emergence into the Firth of Thames in the Thames-Coromandel District of New Zealand`s North Island. The bridge was completed in 1928 and is part of State Highway 25. The swinging span in the middle of the bridge is 43 metres long and with an overall length of 463 metres, the bridge is the longest and oldest single lane bridge within the state highway network.