Forgotten World Highway
This is highway 43, between Stratford and Taumarunui is a heritage trail. It's about 150 km long, with some unsealed road. If you really take your time and make some stops, it will take you about 5 hours. It's got a lot of hills and twists and turns, but it's really worth it. There are some amazing views, lovely gorges, tiny tunnels, waterfalls next to the road and almost nobody there.