Seminary Hill (off Seminary Road, near St. Stephens Road)

The hilltop south of Old Leesburg Road has been three places. In September 1856 the twenty-seven-year-old banker Arthur Herbert ^[1] Source 1 DAC, 'Arthur Herbert — Muckross,' 2020 Website bought 57¼ acres from Elizabeth and Catherine Thompson; he named the estate “Muckross” after the Herberts’ ancestral seat in County Kerry, Ireland. The first house was short-lived. After Federal forces occupied Alexandria on May 24, 1861, the U.S. Army demolished it in 1862 to clear sightlines for Fort Worth, an earthwork built into the hilltop as part of the Defenses of Washington ^[2] Source 2 LOC, Civil War Defenses of Washington Government record .

When Arthur Herbert returned at war’s end he rebuilt directly over the fort. The new house was set partially atop Fort Worth’s powder magazine; its casemates of solid masonry served as cellars, a quiet record of the war preserved in the foundations. He lived at Muckross with his wife Alice Gregory and their five daughters until his death there on February 23, 1919 ^[1] Source 1 DAC, 'Arthur Herbert — Muckross,' 2020 Website .

The estate stayed in family hands through the early twentieth century and was finally subdivided in 1970 for Seminary Ridge, a residential development whose street grid preserves the fort’s memory in the residential street name “Fort Worth Avenue” nearby — though the avenue does not lie on the actual earthwork footprint. The Civil War historical marker now sits on St. Stephens Road west of North Garland Street ^[3] Source 3 HMDB, Fort Worth historical marker, Alexandria, VA Government record , the closest public record of the hilltop’s wartime role. The powder-magazine cellars are gone; the hilltop’s commanding view of Cameron Run and Hunting Creek — the reason Federal engineers chose it in 1861 — remains.

Among Seminary Ridge children of the 1950s and 1960s the property was known as the “Moss Mansion” — a neighborhood corruption of MUCKROSS engraved in the pillars that flanked the entrance from St. Stephens Road. A reminiscence shared in 2024 on a public Alexandria Facebook page describes the property in its final years before demolition: terraced gardens bordered by ancient boxwoods large enough to climb inside, decaying outbuildings holding dog skeletons (or so the children believed of the rumored “Dr. Moss”), and a water tower in the valley that would become upper Fort Williams Parkway. By the writer’s freshman fall in college the hillside was “totally stripped bare, with nothing but clay and concrete to be seen” ^[4] Source 4 Public Facebook reminiscence shared by Michael Guiffre Fannon, 2024 Oral history . The transition from Italianate country house to suburban subdivision had the suddenness of a single season; almost no on-site documentary record of the rebuilt 1867 house survives.

The contemporary residential address 4007 Moss Place, in the post-1970 Seminary Ridge subdivision that replaced the estate, is sometimes marketed under the historic “Muckross” name. No primary-source evidence at the Alexandria Library Special Collections has yet established that the structure currently at 4007 Moss Pl is fabric of the 1856 Herbert house; pending further research, this site treats that address as name-bearing, not house-bearing. ^[5] Source 5 Alexandria Library Special Collections Manuscript