One surprising fact is that the colorful, adventurous era of the old West existed for such a short time. The cattle industry did not begin to develop until after the civil war, when railroads began to penetrate the Plains States and it became possible to send cattle to Eastern markets. But by 1900 the free range had been fenced in and the great cattle boom was over. While working cow hands still exist in the modern West, the cowboy of legend the"American Cavalier' strutted the dusty stage of Western history for only about thirty years