Lake Wairarapa is situated in the southern North Island of New Zealand in the Wairarapa District of the Wellington region. The lake covers an area of 78 km² (48 square miles), making it the third largest lake in the North Island. The nearest town is Featherston about 5 km (3 miles) away.
The area around the lake is quite low as it resides in a plain near the southern coastline of the North Island. Around the lake it is quite swampy and further back is mainly farmland or grassy plains dotted with trees.
The Rimutaka Ranges offers great views of the lake.