Gallery: 1,000 'Vikings' descend on Europe's biggest fire festival

It's no accident that we included Up Helly Aa, the self-proclaimed "Europe's largest fire festival," in our master list of crazy fun things to do in 2013. 

Officially running since the 1880s in Lerwick on the Scottish Shetland Islands, the festival has its roots in an uproarious celebration for sailors and soldiers returning home after weeks at sea. 

Initial ceremonies revolved around a single custom called "tar-barreling" -- knocking together tubs of tar and setting them on fire. 

When that became too dangerous, the annual ceremony was changed to a more elaborate procession with a Viking theme, in commemoration of Shetland's Viking heritage. 

Today, nearly a thousand Guizers (local volunteers "disguised" in Viking costumes) march on the day of the ceremony. 

This year's Up Helly Aa took place on January 29, beginning with marches to the British Legion at 8:30 a.m. and finishing with spectacular torchlight processions and the burning of a replica Viking ship.

Lerwick, Shetland Isles, Scotland; www.uphellyaa.org

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