Back in the age of the mysterious mound builders, perhaps.
It is considered to be the last word in the controversy over the Mound builders' identities.
"What if you turn up mound builders instead of Atlanteans?"
They were followed by people known as Mound Builders about 3,000 years ago.
They were one of several succeeding cultures often referred to as mound builders.
"Mound builders" have more commonly been associated with the mounds in the Americas.
Others recognize a setting among the mound builders as the book's original setting.
None of the imperiled is a mound builder like the river chub.
It was originally settled by the 'mound builder' culture.
He backed three survey groups on Fennis, striving to place the mound builders there.