In the late evening on October 2, 1915, a powerful earthquake rocked a large region of the western United States.

The Pleasant Valley M7.8 earthquake occurred at 10:53 p.m. and was centered in a remote region in north-central Nevada, about 45 miles south of Winnemucca.

It registered maximum shaking intensities of X-XI on the Modified Mercalli scale (a relative shaking rating from 1-12 shown in Roman numerals) and is considered the strongest earthquake in history of Nevada. It was felt as far away as Washington to Mexico and from the Pacific to Colorado, Montana and Arizona.

Sparse buildings and some mine facilities near the epicentral region suffered extensive damage; Winnemucca experienced moderate damage with some collapsed structures.

The largest of two sizable foreshocks earlier that morning registered M6.3 and an intense aftershock sequence lasted for several years.

Spectacular surface fault displacement occurred for over 37 miles along the eastern flank of Pleasant Valley, with maximum offsets of 22 vertical feet.

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