The American Southwest gives new meaning to the word "space." From Houston's Johnson Space Center to New Mexico's Museum of Space History in Alamogordo, near where the Atomic Age began, well, there's a lot of space out there. So plan ahead: carry lots of water and stock up with food at all opportunities. The next place to serve you could be a long, long way down the road. But then start enjoying all that space. It's getting harder to find all the time.

Family Road Trippin'

CLICK HERE to view a map of this itinerary—and 19 other family-centric road trips across these United States. Texas Photo Gallery

Day 1: Houston to San Antonio (197 Miles)
We have no problem with the largest city in Texas. From its high-rise, ultra-modern skyline to the aging grace of the Astrodome, America's first domed baseball stadium, Houston exudes optimism. Nowhere is this more apparent than at the Lyndon B. Johnson Space Center and Space Center Houston (281.244.2100; www.nasa.gov/centers/johnson), a working command center and visitor attraction on the southeastern outskirts of the city. Operated by NASA, the facility tells the story of America's manned flights in space. Although U.S. space flights originate in Florida, this is the spot where the first words ever spoken by a man on the moon arrived back on Earth. The first word was, of course, "Houston," as in "Houston, Tranquility Base here. The Eagle has landed."

Take Off!: Houston's Johnson Space Center (PhotoDisc)

When you've got your feet back on the terrestrial firmament, hit the Houston beltway and start the drive toward San Antonio, about 200 miles west. San Antonio's must-see stop is the Alamo (www.thealamo.org), a small façade that's writ large in the legends of the Southwest (thanks in large part to larger-than-life characters like Davy Crockett—and John Wayne's Hollywood take). The famous little Mission Church that played an instrumental part in Texas' battle for independence from Mexico is but one of a slew of Mission ruins throughout the city. You can take a trolley tour to see them all. Closer to the Alamo and right downtown, another good family spot is the Riverwalk, a shop- and restaurant-lined area along the San Antonio River, which can be covered on foot or by boat.

For your first night on the road, camp at Blazing Star Luxury RV Resort (210.680.7827; www.blazingstarrv.com), about 20 minutes from downtown San Antonio. Here you'll get comfy with year-round wooded sites, groceries, RV supplies, Internet, pools, hot tubs, and a fitness center, among other amenities.