For many visitors, Fairbanks' primary pulling power lies in a natural phenomenon: the Aurora Borealis, better known as the Northern Lights. As solar winds flow across the earth's upper atmosphere, they hit gas molecules which light up, much like the high-vacuum electrical discharge of a neon sign.
What you end up with is a solar-powered light show of waving, diaphanous light streaming across the night sky. In the dead of winter, the aurora often fills the sky for hours. Other nights, 'the event', as many call it, lasts less than 10 minutes.
This polar phenomenon has been seen as far south as Mexico, but Fairbanks is the undisputed aurora capital. The best viewing is from September to April, and it's worth a trip to the outlying hills, away from the city lights.