Seven historic sites across Fairfax County open for free guided tours on Sunday, Sept. 20 and Sunday, Sept. 27, giving Reston-area residents a chance to walk through buildings most people never see inside.

The Fairfax County Park Authority (FCPA) is running the September Sundays Free Tour Series as part of Fairfax250, the county's commemoration of America's 250th anniversary. Sites on the tour include Colvin Run Mill in Great Falls, Ellanor C. Lawrence Park, Green Spring Gardens, Historic Huntley and Sully Historic Site in Chantilly. The series began Sept. 13.

Two stops are buildings rarely accessible to the public.

The Spindle Sears House in Historic Centreville Park is a Sears, Roebuck & Co. "Brentwood Home" kit house the Spindle family built in 1935. The other is the Frying Pan Spring Meeting House at Frying Pan Farm Park, a structure standing by 1791. The Virginia Department of Historic Resources describes the Meeting House as one of the state's oldest surviving Baptist churches, where a racially integrated congregation gathered from its founding. It earned a spot on the National Register of Historic Places in 1991.

The Meeting House and its grounds are not regularly open to visitors. In 1984, the property's last surviving trustee deeded it to the Park Authority, according to FCPA records.

All tours are free. Space is limited, and advance registration is required through the FCPA's Fairfax250 page. Specific tour times were not listed in available materials.

The Park Authority said visitors at the tour sites can experience working mills, historic homes, gardens and farm life, along with stories of freedom seekers whose lives connect the county to the nation's history.

The series is sponsored by the Fairfax County 250th Commission, which the Board of Supervisors created in 2021 to lead anniversary events. Liz Maurer chairs the commission.

Visitors looking for a self-paced option can try the Fairfax250 Adventure Patch, also sponsored by the commission. Participants complete six activities across three themes and earn a commemorative patch. Details are on the same FCPA page.

WTOP reported on the tour series Sept. 12.

Upcoming community events

• Sunday, Sept. 20 and Sunday, Sept. 27: September Sundays Free Tour Series, seven Fairfax County historic sites. Free; registration required at fairfaxcounty.gov/parks.