Heimdall's mighty horn whose sound wakes the gods at Ragnarök.
Gjallarhorn is the mighty signal horn that Heimdallr carries at his post by Bifröst and blows when danger threatens. Its sound is so powerful that it is heard in all nine worlds and will summon the einherjar and gods to the final battle.
In one of mythology's more enigmatic motifs a Gjallarhorn is mentioned as hidden beneath Yggdrasil at Mímir's well, likely Óðinn's horn pledged as payment for a drink of wisdom. The relationship between the two horns is debated.
Attestations
- Völuspá 46
- Heimdallr blows Gjallarhorn and rouses the gods.