- Not to be confused with Gjalerbron.
Gjalerhorn is the mountain to the west of Frostblade Peak in the Howling Fjord. It is home to a mining operation controlled by snobolds. Gjalerbron and Rivenwood are at its southern base, the border with Grizzly Hills to its north. There is an entrance into the mountain at [43.2, 10.6]
- In Norse myth, Gjallarhorn is the "ringing horn" with which the gatekeeper god, Heimdallr, announces Ragnarök.
- At the peak of the mountain, the wreckage of what appears to be a rocket-powered vehicle is half-buried in the snow, surrounded by several gnome-sized skeletons along with empty bottles and fish skeletons, presumably the crew's last meal before dying of exposure and starvation.