Amidon Graves Mystery

It’s one of Sioux Falls’ oldest mysteries: two missing graves, one misunderstood mound, and a reminder that the prairie remembers more than we do.

Judge Joseph Amidon and his son William were killed on August 25, 1862, during the Dakota War, a conflict sparked when the U.S. government failed to uphold treaty obligations, leaving Dakota communities starving and desperate. The Amidons were simply making hay near today’s Pioneer Monument on North Cliff Avenue when a scouting party crossed their path by chance. Their bodies were brought back to the settlement and, according to early accounts, buried near the spot where they fell.

For more than a century, locals believed a long earthen mound, thirty feet by eight feet, scattered with boulders, marked their graves. But in 1991, archaeologists from Augustana College, working with Bruce Blake of the Minnehaha County Historical Society, excavated the site. Soil cores, test pits, even a 21‑foot trench revealed no burials at all... just farm debris and trash piled up over decades.

With that discovery, Blake pieced together a new theory: the Amidons were likely buried in the first city cemetery on the bluff in the Cathedral District. If so, their remains would have been moved to Mount Pleasant Cemetery when all early burials were relocated. But no markers, records, or names match them. Their final resting place remains unknown.

The mystery doesn’t stand alone. Across the Midwest, countless Indigenous burial mounds were plowed under during early settlement flattened before anyone documented who was buried there or what those places meant. The Amidon graves were individual burials, misplaced but remembered. Yet both stories point to the same truth: the land holds memories long after people forget.

Today, the Cathedral District’s quiet streets and historic homes sit atop the earliest heartbeat of Sioux Falls, its first burials, its first tragedies, its first unanswered questions. Somewhere out there, the Amidons still rest. And somewhere beneath fields across the region, so do ancestors whose names we’ll never know.

The prairie keeps its secrets. We just keep trying to listen.