MIAMI, Fla. -

The Port of Miami tunnel boring machine, aka "Harriet," broke through Dodge Island Tuesday morning.

This milestone marks the half-way point in the tunnel boring process, the first of two tunnel tubes to be completed.

Harriet will now be turned around for the trip back to the mainland that will create the second tunnel chamber.

Officials from Miami-Dade County, the City of Miami, Florida Department of Transportation, the Federal Highway Administration, Miami Access Tunnel, Buoygues Civil Works along with the hundreds of workers on the tunnel project were on hand to watch the historic event.

The tunnel project is a public-private partnership between Miami Access Tunnel, FDOT, Miami-Dade County and the City of Miami. Construction began May 2010, and the project is expected to be completed in May 2014.