DOWNTOWN. Let someone else do the driving! You'll see all of San Antonio's sights on these trolley tours without the stress of navigating an unfamiliar city. Opt for the Grand Tour for the most thorough itinerary, or just get the short list on the Highlights Tour. A Hill Country Tour ambles down back roads, and you can even go international on the Mexico shopping tour.

KING WILLIAM DISTRICT. Within this lovely district, leading German merchants settled in the late 19th century. Today, its elegant Victorian mansions and tree-lined streets are a pleasure to behold. Madison, Guenther, and King William streets are particularly pretty for a stroll or drive. Stop in at the Guenther House or Steves Homestead, two historic homes that offer guided tours. The former features a small museum of mill memorabilia, a gift shop, and a restaurant serving fine German pastries and full breakfasts and lunches.

NATURAL BRIDGE CAVERNS. Geological activity and mineral display are something to behold, especially when you have the chance to do it up-close-and-personal. These caverns, discovered 40 years ago, take visitors for an underground glimpse of the earth's silent workings. The 140 million-year-old rock formations continually change, and every millennium, they're different ­ plan your trip accordingly. Attractions include ziplines for the adventurous and rock-panning for the landlocked, not to mention food vendors and a gift shop.

RIVER WALK. If you're tired of strolling up and down the River Walk, why not explore it by boat? Three routes ensure that you'll see everything there is to see, and knowledgeable narrators point out historic sites and dispense practical information (with a soupcon of humor). Charter tours and a more utilitarian river taxi service are also offered. While it's advisable to purchase tickets online, you can also pick them up at Rivercenter Mall, at the Holiday Inn Riverwalk, and across from the Hilton Palacio del Rio Hotel.

RIVER WALK. Also known as Paseo del Rio, this picturesque stretch of San Antonio's downtown is technically a city park but is better recognized as a dining and entertainment haven. Built a full story below street level, it offers three miles of stone pathways that line both banks of the San Antonio River. Some areas are peaceful and quiet while others are noisy and fun with clusters of restaurants, bars, hotels, and even strolling mariachi bands. The area is also pleasant when viewed from river taxis and charter boats, some of which serve dinner.