# The rocks that came down

When the shakes opened the Port Hills, the cliffs threw their stones, and surveyors walked the slopes afterwards and mapped every one. 6,795 pins, 20,284 rocks in all: 12,042 came down, and 7,101 of the ones still sitting wobble under a push.

## The record

- 6,795 survey pins, 20,284 rocks
- Fallen: 12,042 · still in place: 8,002
- Wobble easy: 7,101 · difficult: 3,943 · not tried: 1,788

## The biggest on record

- **1,500 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.587227626321486&lon=172.74246080661717&radius=250)
- **1,125 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.60521575350819&lon=172.72895459303066&radius=250)
- **1,125 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.60524367450108&lon=172.728920072763&radius=250)
- **1,000 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.60860200460684&lon=172.6713660009579&radius=250)
- **1,000 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.614751010906275&lon=172.6607700049711&radius=250)
- **950 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.58049000362301&lon=172.75074999876492&radius=250)
- **750 m³**, still in place · wobbles easy · [the ground](https://www.chch.live/before?lat=-43.58935544712347&lon=172.74777336382454&radius=250)
- **750 m³**, still in place · [the ground](https://www.chch.live/before?lat=-43.60536451246149&lon=172.64906948964793&radius=250)

## The hills’ suburbs

- Sumner: 6,354 rocks counted · 1176 wobble easy · 3792 down already
- Heathcote Valley: 5,632 rocks counted · 279 wobble easy · 3375 down already
- Lyttelton: 1,023 rocks counted · 48 wobble easy · 612 down already
- Mount Pleasant: 1,000 rocks counted · 34 wobble easy · 823 down already
- Hillsborough: 923 rocks counted · 73 wobble easy · 612 down already
- Governors Bay: 772 rocks counted · 139 wobble easy · 136 down already
- Cass Bay: 762 rocks counted · 71 wobble easy · 419 down already
- Cashmere: 510 rocks counted · 57 wobble easy · 212 down already
- Scarborough: 457 rocks counted · 31 wobble easy · 381 down already
- Richmond Hill: 408 rocks counted · 8 wobble easy · 400 down already
- Ferrymead: 400 rocks counted · 47 wobble easy · 326 down already
- Redcliffs: 242 rocks counted · 234 down already
- Huntsbury: 145 rocks counted · 14 wobble easy · 61 down already
- Clifton: 136 rocks counted · 4 wobble easy · 77 down already
- Diamond Harbour: 123 rocks counted · 16 wobble easy · 24 down already

_Each survey pin files under the suburb it sits in: the count of pins, the rocks counted (a pin may stand for a cluster), and how many rocks fell or wobble easy. A pin marks where the survey saw the rock, not where it is now._

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Christchurch City Council open data, the BoulderFieldCapture layer of OpenData/LandCharacteristic, the GNS rockfall survey. A pin marks where the survey saw the rock, not where it is now. A point’s own record: https://www.chch.live/before. The files: https://www.chch.live/boulders.json · https://www.chch.live/boulders.geojson · by suburb: https://www.chch.live/suburb-boulders.json