Hell Kettles is a Site of Special Scientific Interest in the Darlington district of County Durham, England.

[2] Surface runoff and seepage from calcareous springs has created the two pools, one of which is the only body of spring-fed open water in County Durham: there were originally four subsidence depressions, but one filled in and two are now linked in a pond aptly named 'Double Kettle'.

The name "hell-kettle" is often applied to ponds that are popularly believed to be bottomless;[3] these particular ponds are mentioned in Holinshed's Chronicles:[4] There are certeine pits, or rather three little pooles, a mile from Darlington, and a quarter of a mile distant from the These banks which the people call the Kettles of hell, or the diuels Kettles...and, it has been suggested,[5] may have inspired the scene in Lewis Carroll's Alice's Adventures in Wonderland in which Alice tumbles down a rabbit hole.

'Double Kettle' is fed by surface runoff and its water is turbid, supporting only an impoverished surface vegetation of pondweeds, including the alien Canadian pondweed, Elodea canadensis; it is fringed mainly by common reed, Phragmites australis, with some saw-sedge and common club-rush, Scirpus lacustris.

[6] To the south, the smaller 'Croft Kettle' is fed by calcareous subterranean springs and its clear water supports a luxuriant growth of stoneworts; its fringing swamp is dominated by saw-sedge, Cladium mariscus, creating a vegetation type similar to that of the fens of East Anglia and which is found nowhere else in County Durham.