The quake had a duration of approximately 10–20 seconds, and its peak ground acceleration of 1.82 g0 (17.8 m/s2)[7][8] was the highest ever instrumentally recorded in an urban area in North America.[9] Strong ground motion was felt as far away as Las Vegas, Nevada, about 220 miles (350 km) from the epicenter. The peak ground velocity at the Rinaldi Receiving Station was 183 centimetres per second (4.1 mph; 6.6 km/h),[10] the fastest ever recorded.