Valuiki and Mitchurinsk to Rostov-on-Don mainlines. Only one such locomotive was preserved, no. IS21-578, plinthed outside the main railway station in Kyiv in Ukraine. United States Locomotives of a 2-8-4 wheel arrangement were used mainly for hauling fast express freight trains on heavy freight service. They often replaced older 2-8-2 Mikados where more power and speed was required. Six years after the Atchison, Topeka and Santa Fe Railway experimented with the first 2-10-4, the first 2-8-4s were built for the Boston & Albany (B&A) by Lima Locomotive Works in 1925. The railroad's route over the Berkshires was a substantial test for the new locomotives, but the type proved its worth, outpacing the 2-8-2 Mikados already in use there. This mountain range lent its name to the locomotive type, though the Chesapeake and Ohio Railway would settle on the name Kanawha for their 2-8-4s. Buoyed by the success of the demonstrations on the B&A, Lima and ALCO both sold a few hundred of the new locomotive type. The Berkshire type's big boost came in 1934, when the New York, Chicago and St. Louis Railroad (Nickel Plate Road or NKP) received its first 2-8-4s, built to a new design from the Advisory Mechanical Committee (AMC) of the Van Sweringen empire. Under the Van Sweringen umbrella were the Nickel Plate Road, Erie Railroad, Chesapeake and Ohio Railway and Pere Marquette Railway. The AMC's design, based on the Chesapeake and Ohio’s AMC 2-10-4s (which themselves had been based on the Erie Railroad’s own series of 2-8-4s) generated of tractive effort and became the standard design basis for many subsequent Berkshires. The Erie Railroad would come to purchase the largest number of 2-8-4s (though not to the AMC’s design) in the United States, rostering 105. Many later Berkshires differed from their predecessors in their use of greater diameter driving wheels, which assisted greatly in attaining the higher speeds originally sought with the type’s development. Lima's last steam locomotive was also the last American 2-8-4, the NKP's No. 779 of 1949. Some 700 2-8-4s were built for American service, constituting 2% of the steam fleet prior to dieselization and delivering 5% of the nation's freight ton-miles. Coincidentally, ALCO’s last steam locomotives were also berkshires, built in 1948 for the Pittsburgh and Lake Erie Railroad, and towards the end of their short service lives they were transferred to the parent company, the New York Central Railroad. As