In our original episode on Mar-a-Lago, we explored the estate’s over-the-top history and iconic design—but we left out one incredibly important feature. After hearing from many of you, I realized there was a surprising piece of architecture that deserved a deep dive of its own.

In this follow-up, we uncover the forgotten purpose of Mar-a-Lago’s towering structure—and how it wasn’t just decorative. Designed in the 1920s before air conditioning was common, the estate’s 75-foot tower was a marvel of passive cooling, channeling ocean breezes and expelling hot air using the stack effect. We’ll also look at how similar design principles shaped buildings across the U.S., from plantations and adobe homes to 19th-century statehouses and lighthouses. This episode is part correction, part revelation—and it proves just how much history can hide in plain sight.