Head east on Hartshorne Road from Navesink Avenue in Middletown and you’ll eventually come across the cement pillar shown in last week’s Where Have I Seen This?

The pillar, and an identical companion, flank the road at the start of a short causeway between Hartshorne Woods Park and the Navesink River.

Apparently, they once served as gateposts, but we’ve yet to find out for what purpose. Several readers speculated that the gate might have been related to the park’s function as an artillery battery from World War II through the mid-1960s.

Gail Hunton, the historic preservation specialist at the Monmouth County Park System, which operates the 787-acre Hartshorne Woods Park, tends to agree, though she didn’t immediately have a definitive answer.

“The Army was doing some top-secret work up there” and obviously had to secure the property against spies and saboteurs, Hunton says.

Readers with knowledge of the history are invited to comment on this post. (But please don’t reveal the location of this week’s image! For that, drop us a line, please.)

Thank you to all who wrote in: Alycia Yerves, Coleen Dee Berry, Joe Marczak, Stephen Mitchell, Nick Lenczyk, Tom Brenner, Fred Blumberg and Pete Costello, Corey Wagner, Jenny Rossano and Mary White.