Kartchner Caverns State Park
Arizona's Kartchner Caverns State Park is a handicapped accessible active bat cave. Although it is uninhabited for much of the year, it is still inhabited by Myotis bats from late April through late September. The limestone cave has two guided 1-1/2 hour tours, one held year-round and the other from mid-October to mid-April.
P.O. Box 1849
Benson, Arizona 85602
(520) 586-2283
http://azstateparks.com/parks/KACA/tour_info.html
Frio Bat Cave
Although you can not enter it, Texas' Frio bat cave is one of the best places in the world to view bats. From 10 million to 12 million Mexican free-tailed bats leave the narrow cave mouth every evening from spring until fall. The bats are not the only spectacle, as several species of hawks and falcons prey on bats every evening as they exit the cave. Evening bat tours are scheduled from mid-March through mid-September. You must call or email ahead of time to schedule a tour.
P.O. Box 155
Rio Frio, Texas 78879
(830) 966-2320
http://www.hillcountryadventures.com/frio_bat_flight_overview.html
Lewis and Clark State Park
Montana's Lewis and Clark State Park boasts gorgeous and accessible limestone caverns and an active bat population. From April through September, there is a small colony of female and infant western big-eared bats that call the cave home. From May through September, there are guided tours of the caves daily. The caves are not handicapped accessible, but they are open to children 6 and older, and require no special equipment. There are regular and candlelight tours available.
P.O. Box 489
Whitehall, Montana 59759
(406) 287-3541
http://fwp.mt.gov/parks/LewisClarkCaverns/tours.html