Saint Anthony Falls, in Minneapolis, nearly vanished entirely. In 1869, workers digging a hydropower tunnel beneath the riverbed accidentally let the Mississippi pour in, opening a whirlpool that threatened to swallow the falls whole. The fix, a cutoff wall sunk three storeys into the sandstone, worked so well that everyone forgot about it for nearly 150 years, until a historian raised the alarm in 2021.

The falls have always been on the move. Twelve thousand years ago they stood near St. Paul, migrating upstream as the river ate through limestone and soft sandstone beneath. The Dakota called them Owamni Yomni, meaning turbulent waters. They considered the site sacred, once home to Spirit Island, a birthing place for generations of women.

VoiceMap's Minneapolis River Walk tour follows this stretch of the Mississippi, tracing the falls' engineering history, near disappearance and Dakota heritage as it moves along the riverbank.