The 3 November 2002 Mw 7.9 Denali fault earthquake was one of the largest North American earthquakes of the past 100 years. This earthquake, located 330 km to the west of the Yukon-Alaska border, generated 260 reports of shaking and other “unusual effects” to distances of 3500 km across western Canada. Felt intensity for this earthquake ranged from V at communities in the Yukon closest to the epicenter (about 350 km distance), IV across much of the Yukon Territory (distances of 350 to 750 km), III across much of northern British Columbia, to II in southern British Columbia and Alberta (about 2400 km distance). In many instances, people reported feeling nauseous or seasick and having trouble standing. The long-period ground motions generated by this earthquake (displacements greater than ±10 cm were recorded in the Yukon) caused water to spill from swimming pools, generated seiches in lakes and rivers, and affected wells (instances of dirty well water) to distances of 3500 km across western Canada.