Once there was an endless redwood wilderness, populated by only the hardiest of people. Then, the sudden blast of a steam whistle echoed across the canyons and the valleys-the iron horse had arrived in the Santa Cruz Mountains. Driven by the need to transport materials like lumber and lime to the rest of the world, the railroad brought people seeking out new ways of living, from the remote outposts along Bean and Zayante Creeks to the bustling towns of Los Gatos and Santa Cruz. Bridges and tunnels marked the landscape, and each new station, siding and spur signaled activity: businesses,...