Ocean Floor Map

Colonial Ridge map

Undersea ridge: 1,356 m down (GEBCO_2026 grid).

Tap or scroll to load the interactive map

Sea level todayDrag the slider to lower the sea and see the land that would appear.

Sea level in metres below today’s. A simple bathtub model: it lowers the sea everywhere by the same amount and does not simulate how the water would really drain.

Key

Sea depth

  • Deeper than 6,000 m
  • 4,000 to 6,000 m
  • 2,000 to 4,000 m
  • 1,000 to 2,000 m
  • 200 to 1,000 m
  • Shallower than 200 m (the continental shelf)

Land height

  • Land up to 500 m
  • 500 to 2,000 m
  • Above 2,000 m

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  • Seabed exposed when the sea is lowered A dashed white line marks today’s coast.

How to read the map. Darker blue is deeper water. Tap anywhere to see how deep the sea is there, or how high the land is, and the nearest named undersea feature. Depths come from the GEBCO_2026 grid, which in most of the deep ocean is predicted from satellite measurements of the sea surface rather than surveyed by ship, and the map’s tiles are coarser than the grid, so narrow trenches read shallower on the map than their true depth. Not for navigation.

Colonial Ridge at a glance

  • 1,356 mdeep in the grid
  • Undersea ridgetype of feature
  • 45.06° S, 166.93° Elisted point
  • New Zealandnearest country, about 10 km
  • 54 of 112deepest of the ridges in our list

Colonial Ridge is an undersea ridge. In the GEBCO grid it reaches 1,356 m below sea level. That figure is the depth in the grid at its listed centre point, so a typical depth for the feature, not its deepest or shallowest point. The nearest country in our list is New Zealand, about 10 km from its listed point.

Open the main map at its listed point and tap anywhere to read the depth.

How deep is the Colonial Ridge?

The grid figure is 1,356 m. We measured it as the depth in the grid at its listed centre point, so a typical depth for the feature, not its deepest or shallowest point. The GEBCO_2026 grid has a value every 15 arc-seconds, about 460 m at the equator, so a very narrow feature can be a little deeper or shallower in reality than any grid cell shows.

Wikidata has no depth figure for this feature, so the grid is our only source for it.

Among the 112 ridges in our list it ranks 54th by depth. The list is the named features on Wikidata with a position at sea, so it is not every undersea ridge in the world.

About ridges

Undersea ridges are chains of mountains. The mid-ocean ridges are where new seafloor is made, as plates pull apart and hot rock rises to fill the gap.

This site lists 112 ridges, 38 of them with their own indexed page. See all undersea features.

Nearby undersea features

Distances are between listed points. A long feature such as a trench or ridge has a single listed point on Wikidata.

The deepest ridges in our list

Frequently asked questions

How deep is the Colonial Ridge?

In the GEBCO grid the figure is 1,356 m. That is the depth in the grid at its listed centre point, so a typical depth for the feature, not its deepest or shallowest point.

Where is the Colonial Ridge?

Its listed point is 45.06° S, 166.93° E, about 10 km from New Zealand.

Data: depth from the GEBCO_2026 grid. Name and position from Wikidata Q134604904 (CC0). See data sources and licences. The GEBCO Grid should NOT be used for navigation or for any other purpose involving safety at sea.

All undersea features · All oceans and seas · Drain the oceans

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