DENVER (AP) — The Denver area is celebrating the opening of the latest spur in its light rail system.

Trains on the 12-mile west line began running Friday from Union Station in downtown Denver to Golden. It’s aimed at reducing congestion on the 6th Avenue freeway.

People can ride the trains for free on Saturday and stop at station parties all along the route.

It’s the first light rail line that’s part of the Denver Regional Transit District’s multibillion dollar transit expansion known as FasTracks.

The line cost $709.8 million and about $300 million of that was funded by the Federal Transit Administration.

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