Searching county land records, Strickland found one Dyson-owned parcel situated in what had once been Zekiah Manor — the 8,800-acre property owned in 1680 by Calvert, the proprietor of the colony. The archaeologists believed that Calvert would have established the fort on his land. But Strickland still didn't know precisely where.

"After plotting the tracts and overlaying them onto current tax maps, aerial maps, topographic maps and soil maps," Strickland said, "Julie, Mike and I began to try to evaluate. … What would be a good defensive position? Where is the nearest fresh water source?"

They zeroed in on a secluded knoll, a few miles south of Waldorf.

Strickland and Alex Flick, 23, a 2010 graduate of St. Mary's College hired to help, went out in February and began digging test holes.

"On our first day of digging, it was my birthday," Strickland said, "So I told Alex, 'Go find me something nice.' I had little expectation we would find anything." But "less than half an hour later, Alex walks up to me with a 17th-century English white clay tobacco pipe."

By the end of the day they'd added Colonial bottle glass, European flint, Indian pottery and a glass Italian trade bead.

"This is pure 1680s," Luckenbach said — nothing prehistoric, nothing more modern; precisely what Zekiah Fort should contain. "You really get to see how the Native Americans were adapting to the new world they found themselves in."

Zekiah Fort, and what it holds, he said, are "an important piece of the closing story of American Indian life in Maryland."

Maryland weather blog: Frank Roylance on meteorology

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