Mount Baldy is still moving, but its movement has been slowed.

Mount Baldy features high hills of wild, windswept sand, topped by grasses, shrubs and small trees. It rises 126 feet above Lake Michigan at Indiana Dunes National Lakeshore. It is the one dune at the federal lakeshore in northern Indiana that visitors are welcome to climb up and slide down.

But the movement of sand that is altering Mount Baldy is slowing. Lakeshore officials have added barriers to keep visitors on designated trails atop Mount Baldy to stabilize the vegetation on the tallest moving sand dune in the lakeshore.

The lakeshore encompasses 2,182-acre Indiana Dunes State Park and several state-run nature preserves. It is a mosaic of dunes, prairies and bogs at the edge of heavily industrial northern Indiana.

Baldy, a bowl-shaped dune at the eastern end of the federal park, is an impressive sight. From the top, you will see a nearby power plant, steel mills to the west in Gary and, on clear days, the Chicago skyline. You still climb two trails to reach the top of Mount Baldy, but parts of the dune are now off-limits. The southern slope with its half-buried trees above the parking lot is closed, as is a third trail. You can scale the dune from the lakeside or take a trail to the top and then hike down its north face.

These are among the world’s highest freshwater dunes, distinctive for their plant diversity. Strangely, you will find Arctic plants and desert vegetation thriving among about 1,400 plant species.

One of the key plants is marram grass, which pokes up through the sand and thrives in the extreme conditions. The narrow waxy leaves and the dual-purpose root system help it endure high winds, shifting sands and temperatures that range from below freezing to desert-like heat. A single marram grass may spread more than 20 feet in diameter.

The Park Service planted 200,000 marram grass plants in 2012 to anchor the dunes. It relied on volunteers after superstorm Sandy to replant about 30,000 of those plants.

You will find marram grass, sand cherry, wild grapes, bluestem grass, milkweed, cottonwood trees and puccoon flames in what’s called the foredunes. In the middle dunes, the plants include arctic bearberry, jack pine, white pine and common juniper. The oldest dunes are home to black oak, witch hazel and winged sumac.

Between the dunes, you are apt to find low-lying, hummocky wetlands.

Music in the sands

If you are lucky, you will hear “singing sand.” The combination of quartz crystals, moisture, pressure and the friction from your feet on the sand can create a clear, ringing sound that can be heard up to 30 feet away. It might occur once a month when conditions are right, according to park officials.

Among the other highlights are blowouts — places where winds have blown away sand and exposed long-buried trees. One of the biggest blowouts is 300 yards long and can be found at the eastern end of the state park. You can access it from the state park or from Kemil Beach.

The lakeshore offers 45 miles of trails for hiking and bicycling. One of the most rugged is the Cowles Bog Trail — a National Natural Landmark — that runs 5 miles through high dunes, wetlands and oak savannahs.

Don’t miss the great overlook on the Dune Succession Trail along with 200 wooden steps that ascend the dune’s face.

West Beach is the most popular area of the park. You will find fewer people and more solitude farther to the east.

A rich history

There is more than a bit of history at Indiana Dunes. That includes the Chellberg Farmhouse, a brick farmhouse built in 1885 by a Swedish immigrant family after a fire destroyed their wooden farmhouse.

A fur trader, Joseph Bailly, set up a trading post in 1822 along the old Calumet Beach Trail that once connected Chicago and Detroit. His last home survives as a National Historic Landmark. The Bailly Family cemetery dating to 1827 is a half mile north of the homestead.

You can also drive past five houses on Lakefront Drive east of the state park. They were part of the Homes of Tomorrow exhibit at the 1933 World’s Fair in Chicago.