There’s a reason Maryland is called America in miniature — you can go from the ocean to the mountains in just a day’s drive.

One of my favorite ways to explore all Maryland has to offer is by visiting state parks. They let you enjoy hiking, camping, fossil hunting and playgrounds galore.

A few years ago, I set a goal to visit every state park in Maryland. While I’m still chipping away at the more than 70 state parks, there are some where my family and I end up again and again.

My personal preference leans towards those near water, whether that’s rivers, the Chesapeake Bay or the Atlantic Ocean. My least-explored areas are the more mountainous parks in Western Maryland — but they’re on my to-do list for this summer.

Many state parks charge a day-use fee to enter. These fees tend to range between $2 and $5, either by person or by vehicle. There are additional costs for camping, boat launches, renting pavilions and some other activities.

If you’re like me, and plan to visit parks frequently, you may want to consider a Maryland Park Service Annual State Park and Trail Passport. This pass gets you into all the state parks without having to pay the admission fee each time. They cost $75 for Maryland residents or $100 for out-of-state residents, and can be purchased on the Maryland Park Service website.

Pass or no, here are a few state parks worth checking out.

Calvert Cliffs State Park

10540 H.G. Trueman Road, Lusby

Calvert Cliffs State Park in Lusby, about two hours south of Baltimore, has trails and a large playground made of recycled tires — but the real draw is shark teeth.

A 1.8-mile trail through the woods takes you to the shore of the Chesapeake Bay, where you can search through the sand for fossils the waves have broken free from the waterside cliffs. Most are small, and will test your eyesight to find, but people have been known to find large megalodon teeth in the area.

Bring a bucket or other container for carrying back any sandy treasures you find. The park can fill up quickly in the summer, so call ahead to make sure they’re not full.

Assateague State Park

7307 Stephen Decatur Highway, Berlin

Assateague State Park is located on a barrier island bordered by the Atlantic Ocean and Sinepuxent Bay, about 10 miles south of Ocean City. It’s famous for the wild horses that live on the island and roam freely on its beach and marsh areas. While the horses are fun to see, the Department of Natural Resources reminds people not to approach, touch or feed the Assateague horses.

If you’re just planning to swing by the ocean beach for a day, the day-use area has a bathhouse (which is open May to October) as well as a restaurant and concession shop. You can also reserve campsites for a longer stay on the island.

Patapsco Valley State Park

Hilton Area, 1101 Hilton Ave., Catonsville

Patapsco Valley State Park follows along 32 miles of the Patapsco River as it winds between Baltimore and Howard counties, and there are multiple areas of the park to explore and enjoy. The Hilton area in Catonsville, which my family visits regularly, has a large playground made in part with recycled tires as well as newer play equipment. There’s also a small nature center.

The Hollofield area further north near Ellicott City has a playground and trails, including a steep but manageable climb down to the river. The Avalon/Orange Grove area near Halethorpe has an impressive swinging bridge and paved trail, with plenty of places to branch off and explore or have a picnic near the river.

Like other state parks, they can fill up on weekends. So arrive early or call ahead to check if they’re full.

Sandy Point State Park

1100 East College Parkway, Annapolis

Sandy Point State Park in Annapolis sits near the base of the Chesapeake Bay Bridge and offers sweeping views of the water. You can lounge on the sandy beach and swimming is allowed in designated areas, though watch out for jellyfish later in the summer.

There’s a bathhouse with showers and restrooms as well as a playground, picnic areas and spots for fishing and crabbing (you need a license for anyone 16 and older).

Susquehanna State Park

4122 Wilkinson Road, Havre de Grace

Susquehanna State Park is located in Havre de Grace, not far from where the Susquehanna River meets the Chesapeake Bay. It has several hiking trails, and the Department of Natural Resources website says it has some of the most popular mountain biking trails in the state (though I haven’t tried them personally).

There’s also a historic area with the still-working Rock Run Grist Mill, a toll house for a covered bridge that used to span the Susquehanna, and parts of an old railroad track that had run along the river. The park also offers camping sites, or you can reserve small wood cabins.

Jefferson Patterson State Park

10515 Mackall Road, St. Leonard

Jefferson Patterson State Park sits alongside the Patuxent River in St. Leonard, about two hours south of Baltimore. The park, which is managed by the Maryland Department of Planning, has several trails, including a paved one that runs past a replica of an American Indian village as it would have looked in the 1600s. It then continues to the river’s edge, turning into a boardwalk over a marsh portion of the trail.

The park has a unique focus on history, with more than 60 archaeological sites exploring 9,000 years of documented human occupation, according to the park’s website. People can also sign up to participate in the park’s Public Archaeology Program, where they can help dig for items in the field or wash found objects at a conservation lab.

The park also has a visitor center with exhibits on the history of the site as well as a discovery room with activities and hands-on exhibits for kids.