An enormous volume, latest in the publishers ""Regions of America"" series, this is another foray into the history of the West for David Lavender, a veteran of encounters with the Oregon Trail, (Westward Vision, 1963) and early American fur trapping expeditions in the Rockies (Fist in the Wilderness, 1964) and other excursions into the pristine days of plunder and progress. A native of Colorado himself, he hails from the ""camp"" of Telluride (inevitably yclept ""To Hell you ride"" by conductors on the adventurous little railroad). Most agreeably introduced by the author's reminiscences about his childhood (a miraculous Fourth of July when the ""camp needed to whoop""; floods and dripping icicles; sliding down hill on a scoop shovel) this is a guilelessly expansive presentation of movements, migrations, deals, political and profiteering manipulations, tales of heroism, white and indian calms and strife, social mores, contemporary records and accounts and many, many anecdotes, which add up--because of the author's skill with a loose rein-to a fluid, dynamic portrait of a region. Mr. Lavender also, obviously, has a deep affection for the natural endowments of the Rockies and early along forecasts the ""highly organized, ruthless campaign of exploitation."" The last sentence is a stern reminder: "". . . there simply aren't four hundred years of plunder remaining."" Slow train, great view.