In Howard County, Md., a tie to the Declaration of Independence

This residence of a founding father is older than Monticello. It’s at least as impressive as Mount Vernon – maybe more so. And it could be the most important historic house in the nation you’ve never heard of.

Well, there’s a chance some of you know about it. Judging from our mail, there are plenty of readers out there who know that Grover Cleveland was briefly an assistant teacher before he became a lawyer. But Doughoregan Manor is the mansion that time forgot. It’s the ancestral Maryland home of Charles Carroll of Carrollton, the longest-lived and last surviving signer of the Declaration of Independence.

It’s thought to be the only home of a signer still in family hands. And that family has struggled to pay for its upkeep.

(Not interested in old homes, you say? Keep moving – there’s sure to be a story about the Middle East peace process around here somewhere.)

Doughoregan comes to mind because its patriarch, Philip Carroll, died in early September. He was a direct descendant of Charles Carroll, who, besides reaching the age of 95 and surviving until 1832, was the only Roman Catholic to sign the Declaration.

The mansion is located in Howard County, a fast-growing semisuburban area between Baltimore and Washington, D.C. The family has worked so hard at being low-key that many locals don’t know the estate is there. The holdings, at one time more than 10,000 acres, are down to about 900. The family settled there in 1633. Before them, Indians lived on the land.

But upkeep is considerable on a two-story Colonial mansion with sweeping outbuildings. Earlier this decade, the Carrolls struck a deal to sell some remaining acres to a retirement home, but that deal went bust. Now family members have put 500 acres in a county agricultural trust program, which will provide them with $19 million while preserving the open land.

County officials have also approved zoning and other legal changes to allow new homes on 221 acres. That could provide at least $100 million more, which would pay for lots of authentic slate tiles and stained glass for the family chapel.