ST. PAUL  (AP) -- Construction crews are starting a $243 million renovation that will turn St. Paul's historic Union Depot back into a hub for trains and buses.

Demolition begins Tuesday after a groundbreaking ceremony with elected officials including U.S. Rep. Betty McCollum and St. Paul Mayor Chris Coleman. Crews will start clearing space for train tracks and bus lanes.

The renovation will transform the building into a station connecting future light rail and high-speed trains with buses and bicycles.

The construction project is expected to employ 3,000 workers over two years.

The Union Depot was St. Paul's passenger train station for almost half a century until it closed in 1971. In recent years, the building has housed restaurants, offices and condos.

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