Odin decided to visit Jotunheim, and he knew the best way to get there was with is eight-legged steed, Sleipnir. He donned his golden helmet and took Sleipnir down a wild road away from Asgard. Soon, Odin met the giant Hrungnir, who was standing next to his giant horse, Gullfaxi, whose name means “golden-mane.” Hrungnir moved onto the rode to keep Odin from passing.
“Who are you in that golden helmet who rides such a fine horse?” bellowed Hrungnir.
“This is Sleipnir,” replied Odin, “the finest horse in the realms. I’d wager my head that he’s more than a match for any of your clumsy, giant horses.”
Odin’s insult angered Hrungnir. “Sleipnir may be a fine horse, but he’s no match for my Gullfaxi. Let’s race and afterwards, you’ll pay for your insult to Jotunheim’s horses!” Hrungnir leaped astride his horse and ran at Odin.
Odin wheeled Sleipnir around and rode toward Asgard as fast as Sleipnir could manage. Sleipnir was the flash of white lightning in the sky. Gullfaxi was the rumble of thunder following close behind. Odin and Hrungnir reached the Rainbow Bridge, and Hrungnir recognized his mistake too late. Still, he tried to rein in Gullfaxi to no avail.
Heimdall opened the Asgardian gates. Odin made it home. Heimdall couldn’t close the gates fast enough. Hrungnir and Gullfaxi entered the Asgardian courtyard. The gates shut behind the rider and horse, trapping them inside the walls of Asgard.
Contrary to Hrungnir’s fear, the Asgad gods welcomed him. They wouldn’t kill a lone giant who stumbled into their midst, even one as fierce and wicked as Hrungnir. They offered him food, drink and a place to rest before he made the return trip to Jotunheim.
Hrungnir accepted their hospitality. Thor was away from Asgard, so the gods filled his cups with mead for Hrungnir. Thor’s cups were the closest they had to giant-sized drinking vessels. Unfortunately, Hrungnir was not a giant, who could hold his liquor. He quickly became drunk and raged like a mad man.
Sources: The Prose Edda by Snorri Sturluson.
The Definitive Guide to Norse Mythology: The Gods, Heroes, Monsters and Legends of Viking Culture by Finn D. Moore.