From 1941 to 1981, Mono Lake lost half of its volume when four of its tributaries were diverted for Los Angeles's water supply.
— Minden Pictures/Superstock
Mono Lake Tufa State Natural Reserve, California, features tufa towers, limestone formations that rise from the namesake lake.
— Andrea Wyner
Last April, New York State launched a $25 million project to attend to Niagara Falls State Park's urgent infrastructure needs.
Michigan's Recreation Passport Program will get you into Ludington State Park and other Michigan parks for $10 per year. The program has raised $6 million for the parks since 2010.
— David Davis/AGE Fotostock
Cache River State Natural Area in Illinois includes 20 miles of foot trails and a floating boardwalk that leads to the center of Heron Pond.
Red Rocks State Park, Arizona, was targeted for closure in 2010, but fund-raising has helped to keep it open until at least 2013.
— Whitney Tressel
Blackwater Falls State Park is one of West Virginia's most photographed places, but hydraulic fracturing (a.k.a. fracking) may be darkening its future.
With four miles of white-sand beaches, Honeymoon Island State Park, Florida., more than lives up to its romantic monicker.
The 240-mile Katy Trail State Park through Missouri's midsection gets its nickname "Katy" from the former railroad line that it traverses: the Missouri-Kansas-Texas (MKT).
— Justin Leesmann
You could say the Valley of Fire State Park, Nevada, has star quality: It stood in for Mars in the 1990 movie Total Recall.
Ohiopyle State Park, Pennsylvania, with four beautiful waterfalls, may have inspired Frank Lloyd Wright's Fallingwater house, just five miles away.
— Richard Nowitz/National Geographic Stock
Visit these state parks while you still can.