ABANDONED. swamps or bogs with sinkholes scattered about. They eventually drive posts into the sinkholes and build a path to some building hidden in the swamp.

[Snarfquest]

Series of books from '70 or earlier. There's a bog/swamp with sinkholes scattered about. They eventually drive posts into the sinkholes and build a path to some building hidden in the swamp.

[Sue]

"Gone-Away Lake" and "Return To Gone-Away" by Elizabeth Enright?
Plot

Gone-Away Lake starts on a train, traveling through the countryside of western New York state. Portia Blake and her brother Foster are coming to see their favorite cousin, Julian Jarman. Once there, Portia and Julian are walking in the forest when they discover an old Victorian resort community next to a bog. Elderly siblings Mr. Payton and Mrs. Cheever, the town's only inhabitants, soon become friends with the children, who set up a club in an abandoned house. Stories of the days when the bog was a lake called Tarrigo are interspersed with the modern-day adventures of Portia, and Julian, who at first keep the entire place and their new friends a secret. Foster soon discovers their secret and the rest of the members of the Jarman and Blake families also become acquainted with the charms of Gone-Away and its inhabitants.

[Snarfquest]

Sue wrote: ""Gone-Away Lake" and "Return To Gone-Away" by Elizabeth Enright?


Sounds possible. I'll check into it some more.

[Lobstergirl, au gratin]

Snarfquest, are you still looking for this series? Was it what Sue suggested?

[Lobstergirl, au gratin]

Snarfquest hasn't responded since 2011. Moving to Abandoned.