Miami was on the cusp of a new real-estate boom. A developer hoping to build a pair of condo towers razed some rattletrap apartments in Brickell that had long marred a spectacular site, right where the Miami River meets Biscayne Bay.
What the 1998 demolition unexpectedly uncovered roiled Miami and provoked a worldwide outcry — a mysterious set of 24 holes carved into the limestone bedrock in a perfect circle, 38 feet in diameter.
What was it? A landing pad for aliens? A remnant from an ancient civilization, Miami’s Stonehenge? The drain field for the old septic tank sitting on the circle’s edge?…