Pilot/Signal Station established on Cave Rock

This landmark, known as Tuawera or Cave Rock, has been a significant feature here at the outlet of the Heathcote and Avon Rivers estuary in Sumner for a long time. It's a large, isolated rock formed from the eroded remains of a lava flow, and it’s named for the clefts that cut through it. While Captain Thomas of the Canterbury Association initially called it Cass Rock, after one of his surveyors, it quickly became known as Cave Rock due to popular usage.

From the 1860s until the early twentieth century, a pilot/signal station on top of this rock helped guide vessels across the Sumner bar. The Canterbury Provincial Government appointed a pilot in 1864 and put a signal mast up here to indicate the tide’s status. Joseph Day, the second pilot, served for over two decades starting in 1867. The stone pilot/signal station building itself was constructed on top of Cave Rock in 1898. It not only housed signal equipment but also a foghorn to call the Sumner lifeboat crew, whose shed was right next to the rock. There's a plaque on the building commemorating Joseph Day. The Lyttleton Harbour Board stopped running the station in 1914, and the Sumner Lifeboat Brigade has continued to maintain the mast and station, even keeping radio-telephone equipment in the building until recently.

The area around the rock also saw significant development for beautification. In 1905, the Sumner Borough Council decided to create an esplanade, and after WWI, a comprehensive plan included the Sumner War Memorial, which involved stone pedestals with lamp standards, a sea wall, and landscaping carried out between 1923 and 1926. A 1902 memorial for the coronation and the South African/Boer War was even relocated here in 1925. In 1935, a donation allowed for the construction of the Sumner Clock Tower and another section of the sea wall.

The rock was damaged by the Canterbury earthquakes between 2010 and 2012, and remedial work was done with Ngāi Tahu and the Christchurch City Council to remove loose rock. For Māori, Tuawera means ‘cut down as if by fire,’ a name linked to a story from the Kā Huru Manu Ngāi Tahu Atlas about people who died after eating a beached whale.