adjacent properties and moving freight facilities. Construction stalled during World War I, and resumed in 1919. The station finally opened on May 16, 1925, twelve years after construction began; some viaduct work continued into 1927. The construction cost, funded by the railroad companies involved, was projected to be $65 million, but ended up costing $75 million. Construction was delayed several times by World War I, labor shortages and strikes. The construction of the station also involved the demolition and relocation of some previously existing buildings such as the Butler Brothers Warehouse along the Chicago River. It is one of about a dozen monumental Beaux-Arts railroad stations that were among the most complicated architectural programs of the era called the "American Renaissance", combining traditional architecture with engineering technology, circulation patterning and urban planning. Union Station was hailed as an outstanding achievement in railroad facility planning at the time. Wartime, decline, and resurgence During World War II, Union Station was at its busiest, handling as many as 300 trains and 100,000 passengers daily, many of them soldiers. Illustrator Norman Rockwell captured this era with his cover painting for a December 1944 issue of The Saturday Evening Post, depicting the station jammed with Christmas travelers. After the war, the growth of highway construction and private ownership of automobiles caused a severe decline in American passenger-rail ridership, including at Union Station. In 1969, the station's owner demolished the concourse building, making way for a modern office tower. A new and modernized, though less grand, concourse was constructed beneath the tower. In May 1971, the national railroad Amtrak was formed to take over long-distance passenger train service, while commuter trains remained privately operated. In 1980, the station's Fred Harvey restaurant experienced a large fire. The space was damaged, windows on Clinton Street were destroyed, and the space was left vacant since then. In 1984, Amtrak bought out the shares of Chicago Union Station Company held by Burlington Northern (successor to the Burlington Route) and the Milwaukee Road, becoming sole owner of the station. In the 1990s, Lucien Lagrange Associates made some patchwork renovations, including to the Great Hall and its skylight, which had been blacked-out since World War II. Restoration of Union Station continued. Numerous spaces within the station had yet to be renovated, and many sat unused, especially within the station building. 21st century After the September 11, 2001 attacks, Amtrak closed the pair