The Nero was a steel steam collier, built in 1895. It was acquired by the United States Navy for service as a collier and supply ship, Nero was part of a fleet organized to meet logistic demands created by far-flung U.S. Naval Operations in the Spanish–American War. Following conversion at Mare Island Navy Yard, the ship departed San Francisco on 23 June 1898 for the Philippines, in company with the monitor Monadnock. Sailing by way of Honolulu and Guam, the collier arrived in Manila on 14 August and remained there supporting U.S. forces occupying the Philippines until departing on 4 October on a coaling voyage, steaming to Taku, China and Nagasaki, Japan, before returning to Cavite on 20 November. She was placed out of commission in January of 1899 and then recommissioned on 10 April. She sailed five days later for the Hawaiian Islands for deep sea soundings, then steamed via Guam to the Philippines arriving at Cavite on 4 August. There she coaled various naval vessels until sailing on 9 September for Yokohama to continue deep sea sounding stopping in Guam on 10 September. The collier got under way for the west coast on 24 September, stopping at Guam and Honolulu and arriving Mare Island on 15 February 1900. During this voyage she took a sounding in the area of the Challenger Deep, recording a depth of 5269 fathoms (9,636 m, 31,614 ft), the greatest depth recorded at that time. She was decommissioned on 20 May 1899 and recommissioned several times before her final decommissioning in 1920.