If the thick, concrete walls of Fort Casey could talk, they would tell remarkable stories.

There is a lot of history surrounding the impressive structure. The thickness of the concrete and the size of the guns are quite jaw-dropping.

Fort Casey was built in the late 1890s, and with Fort Flagler and Fort Warden formed the Triangle of Fire.

The three forts guarded the entrance to Admiralty Inlet, protecting military targets in Puget Sound.

Fort Casey, which never fired a round at an enemy target, was used for drilling troops in World War I and World War II.

Fort Casey’s military muscle was the seven 10-inch guns along the batteries’ walls. The guns were mounted on disappearing carriages, meaning they could be pulled down behind thick concrete after each round was fired. In addition to the 10-inch guns, there were 12 smaller guns and 16 mortars.

After World War I, the Army mothballed Fort Casey. Many of the 10-inch and 6-inch guns were sent to France. By 1945, all the armament had been scrapped and melted down.

The fort was revived during World War II as anti-aircraft guns were mounted in the old emplacements. The return to action was short-lived as the fort was again placed in caretaker status in 1950.

In 1956, the Washington State Parks and Recreation Commission purchased Fort Casey from the General Service Administration. In 1968, the commission purchased the two 10-inch guns that are in place today from Fort Wint in the Philippines.

From a visitor’s standpoint, there are a couple of ways to attack the fort.

For the purpose of this writing, explore the upper fort first, then venture to the ground level installations.

There are numerous opportunities to climb down narrow concrete staircases or ladders. Watch your step because many of the stairways do not have railings and the surroundings are nothing but thick concrete.

Distance: 1 1/4 miles

Destination: Loop trail

Difficulty: Easy

Elevation gain: None

Getting there: From Highway 20 in Coupeville, turn south on Engle Road and reach the park in 3 1/4 miles.

The Trek: After parking in the lot, set out to the northwest end of the fort and the massive gun at the end of the battery.

Traipse up the hill at the fort’s northwest end. Once atop, head toward the 10-inch disappearing carriage gun. The size of the gun is astonishing. During its time, it was one of the most powerful weapons on the planet.

The gun fired 617-pound projectiles up to 5 1/2 miles.

Continuing along atop the ramparts, reach another 10-inch gun.

This one is in the lowered position as if it is being loaded. A veteran crew could load, raise and fire the behemoth every 52 seconds.

Battery Moore is next.

It’s nothing but a large, open area where a massive gun used to sit. The heavy, iron rings attached to the wall are maintenance rings. The rings, along with a series of pulleys and ropes, were used to remove and replace the 33-ton gun barrels from their carriages.

The two-inch pipes in the wall are communication tubes. Each tube comes from a room below, where orders were received.

Light shields hooked to the railings illuminated the gun battery. The heavy, black cranes behind the railings were used to raise and lower shells if the elevator failed.

The next battery is Kingsbury. It housed 10-inch guns, but was later modified to accommodate 3-inch anti-aircraft guns.

Make your way around the edge of Battery Kingsbury, then descend to ground level. Once down, head to the right through a concrete archway, passing a series of thick — and locked — metal doors.

Battery Valleu housed four 6-inch disappearing carriage guns used to defend the harbor below. The concrete bulge at the top of the wall is a deflecting shield, used to protect troops from incoming fire. Of course, the shields never saved a soul since the fort was never fired upon or fired a shot in combat.

Continuing along, a slight hill leads to Battery Trevor where 3-inch guns protected the harbor. The pair of imposing 3-inch rapid-fire guns housed there today were brought from the Philippines.

Across the road from Battery Trevor is a short tunnel that leads to a metal door. Behind the locked door lies the the fort’s communication center. The room is protected by a concussion chamber, a 2-foot cushion of air. The entire center is below ground in order to absorb the shock of incoming shells. The chamber was built to survive a direct hit.

Continuing on, the path leads past maintenance residences. A trailhead to the right leads to a pair of earthen mortar embattlements. Battery Alexander Schneck and Battery Seymour each housed eight 12-inch mortars.

Retrace your steps, passing the entrance to the communications center. About 150 feet farther, come to a wooden staircase. Head up it to the primary observing stations.

Venturing into the one structure that can be entered, one is afforded a glimpse of what it was like to look over the top of the fort through narrow, 6-inch gaps in the concrete in search of enemy ships.

Climb out of the structure and locate another wooden staircase leading to the ground west of the fort. Head toward the fort to explore its ground level.

Pass the first of many doors and hallways. These large rooms stored oil and tools.

The arched doorways to the right lead to the shell and powder rooms. Across from these rooms are the elevator shafts in which the shells and bags of gun powder were lifted to the upper level.

There are plenty of opportunities to venture into the bowels of Fort Casey. Make sure to bring a flashlight because many of the rooms are pitch black. A maze of corridors lead into and out of the rooms.

Between Battery Kingsbury and Battery Moore is the battery commander’s station. There are two concrete towers. However, only one can be explored. These were part of a series of checkpoints where soldiers calculated the firing position of the guns.

A narrow concrete staircase leads up to a walkway. To the left, the walkway leads to the main body of the fort.

Go to the right. Venture up another flight of narrow stairs. A sharp turn to the right leads into the tiny, concrete atop one of the towers. From inside this structure, the command to fire was given.

From here, continue to explore the extensive ramparts or trek across the massive field back to the rig.