Because the town of San Luis Obispo is not visible from U.S. 101, even many Californians don't know that it's more than another fast food-and-gasoline stopover on the highway. But its "secret" location is part of what helps this relaxed yet vital college town keep its charm and character intact -- it has much of the appeal that defined Santa Barbara a few decades ago.San Luis Obispo (SLO to locals) is tucked into the mountains about halfway between San Francisco and Los Angeles. It's surrounded by green, pristine mountain ranges and filled with a mix of college kids (Cal Poly), big city transplants, dotcom entrepreneurs, and agricultural folk.The town grew up around an 18th-century mission, and its dozens of historic landmarks, Victorian homes, shops, and restaurants are its primary attractions for visitors. Today, it's still quaint, almost undiscovered, and best ventured on foot. It also makes a good base for exploration of the region as a whole. To the west of town, a short drive away, are some of the state's prettiest swimming beaches; to the north and south you'll find the Central Coast's Wine Country, home to dozens of respectable wineries and bucolic scenery.