The headwaters of the Ruamahanga river sit high in the Tararua Ranges, the mountains that stand as the western border to the Wairarapa. The Ruamahanga has wound its way down through the Wairarapa valley for aeons carving out a meandering path of silty loams that make a great grape-growing region.
The Martinborough and Gladstone Wairarapa sub-regions are well-known and to the north of Masterton is Opaki. Opaki has its own distinct combination of terroir and microclimate. Opaki is the home of Loopline.