Then, between those mounds, indigenous gardeners grow squash ... Taken together, these crops are known as the Three Sisters. They're all part of a broader system known as companion planting ...

There are various layout options for a Three Sisters Garden, each with its own merits. The classic approach involves first planting corn seeds in mounds or hills spaced several feet apart.

“Looking at the photograph, it really epitomizes who we are as sisters,” Pamela Cook tells CNN Travel today. “Us three. Laughing like that. It’s a photo I held onto for the longest time.