It was a somewhat shorter day — our last day, sadly — touring around Ireland. This week we went west, and then worked our way north. This evening we have to drive back down to Dublin. We’re flying out tomorrow morning. But that’s tomorrow, and there’s still today. And we have a few more sites to see.

When you go to Dunree Head you’re really going to Fort Dunree. There are several old barracks, the view of the water, Lough Swilly, below and the Fanad Peninsula across the way.

There’s a museum, and a few historical pieces outside on display. Your basic fort features, really. Like, for instance, the 90 cm carbon arc searchlight. Their predecessors were put in early in the 20th century, these were installed in 1938. They were intended to light up enemy ships and assisting the Royal Navy steamers.

The light was so bright it lit up the Ballmastocker Beach we saw yesterday and the village across the way. That’s more than three miles as the crow flies. The story they tell is that you could read your newspaper, at night, from the strength of that light.

The light was manually moved. A soldier stood off to the side several feet and steered the thing around. He was stationed to the side because of the heat the light generated.

You send some electricity through carbon rods and the reflection off the concave mirror does the real work. It could be used as a pinpoint light, or in a moveable wider arc, which turned all of night into day on the water. There are two of these on display, at least one of them would still work. They last used it in a 2011 ceremony.

There are also two QF 12 pounder CWT guns, made by the Elswick Ordnance Company in 1893 and installed here in 1925. The idea behind this weapon was harbor defense against small vessels. They were in service until 1956.

The gunner stood to the left of the weapon. He threw his arm over the shoulder piece, trying his best to look cool. The left hand elevated and depressed the barrel. The right hand rested on a pistol grip, and there he fingered the trigger.

It fired a 3-inch shell, and could average a round down range ever four seconds.

Another key element of the fort was the Mark XVII sea mine.

This is a contact mine, the standard British armament. If your ship bumped up against this your ship would go boom. It was an update on World War I British mines, an evolution from their German counterparts.

There were switches in those horns, now painted red, and this was the standard device during World War 2. Here, they were used defensively, meant to deny access to the waterways. (Historians still debate their effectiveness.) Inside of the mine was a mix of ammonium nitrate and TNT which apparently made for a lower quality explosive. The explosive charge could range between 320 and 500 pounds of explosives. I have no frame of reference for what that means.

In the old rooms of the fort there are little displays, highlighting things like the uniforms and tools and the forge that were all fixtures of the place when it was in active service, which was the case between 1798 (We’ve seen multiple references on our trip to the French fleet that came in to support the Irish Rebellion at the turn of the 18th century.) until after World War 2.

The water here is an important geological feature, one of just three glacial fjords on the island. The water is deep, and there is a sheltered, safe harbor to the left as you look at the photo above. If you sailed to the right, you’re quickly in the transatlantic shipping routes. The British used Lough Swilly’s deep water for much of that time. And here, on top of this cliff, close to the mouth of waterway, the fort commands the best views and any traffic that tried to come through. During the Great War, they erected a boom across the water to protect the British Grand Fleet from a U-boat attack. The British gave over the fort over after the Irish gained independence.

This was the last place handed over to the Irish. There was a brief, small ceremony on Oct. 3, 1938. Not a lot of people saw it, but there was romance and pageantry. A major marched 32 men from the 17th Heavy Battery Royal Artillery to the peak of the fort. Waiting there were 26 men from the 5th Coast Defence Battery Artillery Corps of Ireland.

It was a cold and windy day. It was October, over the North Atlantic. They’re all hunched over with a certain sort of military acceptance and proficiency.

The Union flag was lowered, the Irish tricolour was raised. Sergeant Arthur King lowered the British flag. Quartermaster-Sergeant Michael McLaughlin raised the Irish flag. They were brothers-in-law.

King married a local girl. And the way the signage reads, not everyone was in on the moment. He said they were “keeping this fort in the family” and explained that he was related, by marriage to McLaughlin.

McLaughlin had signed up at 19, in 1922. He stayed on here until 1940, when his service took him to Dublin. He stayed in the Irish Army for another decade after that. When the quartermaster sergeant died his coffin was draped in the flag he hoisted here in October, 1938.

After World War 2 the Irish coastal defense forts were reduced in size and then closed. The guns were fired in their last training exercise in 1964. They were never fired in anger.

In 1989 Fort Dunree was considered strategically unnecessary. The next year, it was formally closed as a base. There was a gale blowing over the Atlantic that June day, but the waters here were said to be perfectly calm. The flag was lowered by a man named Captain William Donagh. He gave the flag to his father, Major General Bill Donagh, pictured above, who had been the officer in charge when the Irish took control in 1938, 52 years earlier.

The place was already a museum by then, since 1986 in fact. When they opened the museum, it served as a reunion, of sorts, for the men who’d served here. They gathered together for this photograph.

That photo was taken 40 years ago. They could tell a lot more stories beyond the excellent signs inside, I’m sure. Hopefully someone jotted them all down.