Natural Bridge Caverns
San Antonio, TX · Texas Hill Country$$
Four college students went looking for passages off a sinkhole in 1960 and broke through into the largest commercial cavern in Texas, named for the 60-foot limestone bridge…

Photo: William L. Farr / CC BY-SA 4.0 · source
Padre Island National Seashore covers 66 miles of Gulf beach at the end of Park Road 22 on North Padre Island, Texas. You can drive and camp right on the sand. Two-wheel drive is allowed on North Beach and the first five miles of South Beach. Past mile marker 5 you'll want four-wheel drive, and that's how you reach Little Shell and Big Shell, about 20 miles down South Beach, where shells pile up after a big storm or a very low tide. South Padre Island is a separate island across Mansfield Channel, three to four hours away by road. Between mid-June and August, Kemp's ridley hatchlings are usually released on Malaquite Beach at 6:45 a.m., and the Hatchling Hotline, (361) 949-7163, says which mornings.
Others worth the drive in Texas.
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