You can walk through 100-year-old flood ruins minutes from downtown Baltimore

It’s all tucked inside a 32-mile river valley

Patapsco Valley State Park stretches 32 miles along the Patapsco River, just southwest of Baltimore, and most people who live nearby have no idea what’s in there.

The valley holds waterfalls, swinging bridges, railroad ruins, and the stone foundations of mill towns that floods erased more than a century ago. You can spend a full day here and barely scratch it.

But the deeper you go, the more the valley gives you.

Maryland’s oldest state park started as a forest reserve

The park traces its roots to 1907, when it was set aside as the Patapsco Forest Reserve. That makes it Maryland’s oldest state park.

The valley it protects was no untouched wilderness, though. Long before the park existed, mills and factories lined this river.

And before those, this is where America ran its first common-carrier railroad. Floods over the years washed much of that history away, but the ruins stayed.

Wayside signs in the Avalon and Orange Grove areas walk you through what the valley used to look like.

Over 200 miles of trails cut through the valley

The park covers more than 16,000 acres spread across eight separate recreation areas, and more than 200 miles of trails run through it. About 70 of those miles are maintained routes.

You’ll find flat, easy paths along the river and rugged climbs up the surrounding hills, often in the same area. Some trails are hiker-only.

Many others are open to bikes and horses.

The paved Grist Mill Trail is a good starting point if you’re with kids or want something relaxed that still takes you deep into the park.

Cascade Falls changes with every season you visit

In the Orange Grove area, a marked trail leads you from the last parking lot back to Cascade Falls. The water drops about 10 to 15 feet down a rock face into a shallow pool below.

It’s not a roaring waterfall, but that’s part of the appeal. The woods wrap around it, and the whole spot invites you to slow down.

Come in summer and it’s cool and green. Come in winter and ice forms on the rock face.

The falls look like a different place depending on when you show up.

Two swinging bridges give you a different kind of river crossing

At Orange Grove, a wooden swinging bridge crosses the Patapsco River about 1.6 miles from Avalon. It sways as you walk across, and the river runs below you through gaps in the planks.

Mill workers once used a bridge at this same spot to get from their homes to the mills on the other side. A second swinging bridge opened in 2006 at the far end of the Grist Mill Trail.

Both draw plenty of foot traffic on weekends, and for good reason.

Stone ruins of the Orange Grove mill sit near the railroad tracks

Cross the swinging bridge and you’ll find the granite foundations of the Orange Grove Flour Mill.

It went up in 1856 and at its peak was one of the largest flour mills in the region, known for a product called Patapsco Superlative Flour. A fire on May 1, 1905, took it down.

What’s left are the foundation walls, solid and overgrown, sitting right beside an active railroad line. Stay back from the tracks when you walk through.

The trains still come through here regularly.

A 612-foot stone bridge built in 1835 still carries trains today

The Thomas Viaduct stands in the Avalon area, and it’s hard to believe it’s nearly 200 years old. Finished in 1835, it was the first multiple-arched stone railroad bridge built in the United States.

The engineers built it on a curve, which was considered a remarkable achievement at the time. It runs about 612 feet long and rises roughly 60 feet above the river.

Active trains still cross it. You can get good views from the trail below, but keep your distance from the tracks.

Foundations and stone walls reveal the valley’s lost mill towns

The Patapsco Valley once held whole communities. The town of Orange Grove eventually faded and got absorbed into the park.

The Daniels area was a cotton-mill town that made canvas tents during the Civil War.

Now you walk through what used to be streets and yards, and every so often you spot a stone wall half-buried in the hillside or a foundation covered in moss.

In 2018, a former dam site upstream from Orange Grove was removed to help fish move freely through the river again.

Fish the river or paddle the calm stretch near Daniels

The Patapsco River runs through most of the park, and anglers pull trout and bass from its calmer stretches. The water near the Daniels area works well for canoes and kayaks.

You can reach the river from several parking areas throughout the park.

Some sections post signs prohibiting swimming for safety, so pay attention when you get to the water.

If you want a quiet morning outdoors, getting on the river early before the weekend crowd arrives makes a real difference.

Walk, bike, or ride a horse through most of the trail system

Most of the park’s trails are open to mountain bikes, which draws riders from across the region. The Grist Mill Trail is the easy option, flat and paved, good for casual riders and families rolling along together.

If you want something with more climb to it, the wooded hillside trails deliver.

Horseback riding is allowed on designated trails throughout the park, and the network gives riders enough variety to put together a solid route.

Bring water for yourself and your horse, and stick to the marked paths.

Picnic shelters, playgrounds, and a nature center fill out the day

The Hilton and Hollofield areas have picnic shelters, playgrounds, and overlooks above the river valley.

The nature center in the Hilton area gives kids something hands-on, and the history center in Avalon has exhibits on the valley’s past. Restrooms and parking are easy to find throughout the park.

Large groups can reserve shelters. If you’re planning a full day with kids, this park doesn’t run out of things to do.

The eight separate recreation areas mean you can keep changing the scenery without ever leaving.

Barred owls call through the trees, even in broad daylight

Deer move through the wooded trails year-round, and the park is home to barred owls that call during the day, which surprises most people who hear one.

The overlook at Hollofield stretches out over the river valley below. Fall turns the hillsides red and yellow, and it’s one of the better times to walk the trails here.

Spring opens up the creek crossings and keeps the waterfalls running well.

Even a midweek visit in summer finds the forest cool under the canopy, with the river audible from most of the lower trails.

Visit Patapsco Valley State Park in Ellicott City, Maryland

You can reach the park from I-695 and I-70 via U.S. Route 40.

The main park office sits at 8020 Baltimore National Pike, Ellicott City, Md. Each recreation area has its own entrance, and no internal roads connect them, so decide which area you want before you head out.

The park is open daily from 9 a.m. to sunset.

Entrance fees are lower for Maryland residents. Avalon, Hollofield, and Daniels fill up early on summer weekends, so get there before 10 a.m.

This article was created with AI assistance and human editing.

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