A Civil War tunnel was discovered at the site of CoStar's new building

Construction workers discovered a 44-foot-long, Civil War-era tunnel on the site of CoStar's new riverfront building.

What's happening: It most likely served as a storm drain for overflow from nearby canals, archaeologist David Dutton told WRIC.

What they're saying: CoStar CEO Andy Florance told the station that the company hopes to preserve elements of the tunnel for display in the new 26-story building.

• "Good and bad happened there and it is exciting when you discover something like that tunnel, and it just brings that rich history of Richmond to life," he said.