The 21st Show

Mysterious Alton Tunnel

City of Alton

City of Alton Reginald Hardwick/Illinois Newsroom

In Alton, along the Mississippi River, a homeowner made an unusual discovery: a mysterious tunnel, made of bricks, that experts have dated to the 1840s. The 21st spoke with the homeowner and hear how the tunnel was found and some of the hypotheses for why the tunnel was built.


Gary Machens, Farmer and Alton, Illinois resident who discovered a 19th century-era tunnel beneath his property.

Prepared for web by Zainab Qureshi

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