Ring Lake is the largest body of water in Coriopolis, and the only one that circumscribes the habitat: it runs the entire way around the cylinder as a continuous band, closing on itself. It lies in the southern half of the habitat and forms the northern boundary of the Southern Park.

Because the lake encircles the cylinder, it has no far shore in the terrestrial sense — only a northern and a southern one — and a vessel holding a constant heading along it returns to its starting point. The circuit is a standard recreational passage.

Northern shore#

The northern shore is the most desirable residential frontage in Coriopolis and is lined with large houses. The shoreline is heavily indented; many of the inlets are backed by sheer cliffs, and tunnels driven through them allow vessels to pass from the lake into a network of underground waterways connecting the surface lakes of the interior. The result is that a substantial fraction of the habitat’s fresh water is navigable without surfacing, and that lakefront property on Ring Lake is in practice property on the whole water system.

Southern shore#

The southern shore abuts the Southern Park and is undeveloped by ordinance. The contrast across a few kilometers of water — mansions on one side, managed wilderness on the other — is among the most photographed views in the habitat.

The lake also served as a datum during the bombing crisis; the tornadoes generated by the second detonation drew their visible outline partly from water vacuumed off its surface.

Lightning displays#

A mast rising from open water near the middle of the band carries the ground electrode of Coriopolis’s engineered lightning installation; its counter-spire descends from the sky 2 km overhead. Scheduled displays strike real bolts down the corridor between them, over water and clear of both shores, and the surface beneath is closed to vessels while the system is charged.