1855 Wairarapa earthquake

The evening of 23 January 1855 was the end of a two-day holiday, the 15th anniversary of Wellington’s founding. Shortly after 9 p.m. a violent earthquake began; in Wellington the main shock lasted for at least 50 seconds. People fled outdoors, where they remained for the night in tents and makeshift beds, as incessant aftershocks rocked the area – one person counted 250 in the first 11 hours. The aftershocks would continue for months. For the first day after the main quake, as far away as New Plymouth an almost continuous vibration could be felt by people sitting, or when leaning against walls.

The earthquake was caused by movement along at least 140 kilometres of the Wairarapa Fault, along the eastern edge of the Rimutaka Range. About 5,000 square kilometres of land west of the fault was lifted up and tilted. The southern end of the Rimutaka Range rose by over 6 metres, but the uplift decreased westward to near zero along the west coast of the Wellington peninsula. Across Cook Strait, the seaward end of the Wairau valley subsided over a metre. Land also shifted over 18 metres horizontally along the Wairarapa Fault.