Meantime the neighborhood was invaded by prospectors from both sides. The Cook Inlet gold fields were exploited in 1894. Two years later W.A. Dickey and his partner, Monks, two young Princeton graduates, exploring north from their workings, recognized the mountain's commanding proportions and named it Mount McKinley, by which it rapidly became known, and was entered on the early maps. With crude instruments improvised on the spot, Dickey estimated the mountain's height as twenty thousand feet--a real achievement. When Belmore Browne, who climbed the great peak in 1912, asked Dickey why he chose the name, Dickey told him that he was so disgusted with the free-silver arguments of men travelling with him that he named the mountain after the most ardent gold-standard man he knew. The War Department sent several parties to the region during the next few years to explore, and the United States Geological Survey, beginning in 1898 with the Eldridge-Muldrow party, has had topographical and geological parties in the region almost continuously since. In 1915 the Government began the railroad from Seward to Fairbanks. Its course lies from Cook Inlet up the Susitna River to the headwaters of the Nenana River, where it crosses the range. This will make access to the region easy and comfortable. It was to safeguard the enormous game herds from the hordes of hunters which the railroad was expected to bring rather than to conserve an alpine region scenically unequalled that Congress set aside twenty-two hundred square miles under the name of the Mount McKinley National Park. From the white sides of McKinley and his giant neighbors descend glaciers of enormous bulk and great length. Their waters drain on the east and south, through the Susitna River and its tributaries, into the Pacific; and on the north and west, through tributaries of the Yukon and Kuskokwim, into Bering Sea. The south side of McKinley is forbidding in the extreme, but its north and west fronts pass abruptly into a plateau of gravels, sands, and silts twenty-five hundred to three thousand feet in altitude, whose gentle valleys lead the traveller up to the very sides of the granite monster, and whose mosses and grasses pasture the caribou.