Gallup University campus, The River City Star riverboat landing, National Park Service Midwest Region headquarters, new high-rise headquarters towers for First National Bank of Omaha, Union Pacific Railroad, TD Ameritrade Park, and hundreds of condominium units. The First National Bank of Omaha tower is the tallest building between Denver and Minneapolis, surpassing its tallest rival in Kansas City by one foot. On Wednesday, December 5, 2007, a mass shooting occurred at the Von Maur department store in the Westroads Mall in Omaha. Nineteen-year-old Robert A. Hawkins killed nine people (including himself) and wounded four, two of them critically. It was the deadliest mass murder in Nebraska since the rampage of Charles Starkweather in 1958. On Thursday, October 1, 2015, ConAgra Foods (a Fortune 500 company) announced that it was moving its corporate headquarters from Omaha to Chicago. ConAgra estimated that out of its 2,500 salaried workers within Omaha, 300 to 350 jobs would move to the Chicago area and another 1,000 would be eliminated. It was initially unclear what would happen to ConAgra's downtown corporate campus. Historic Landmarks Omaha has designated numerous historic structures and sites as city landmarks, including some that date from before the city's founding. Some sites are also recognized as of national importance and listed on the National Register of Historic Places. The site of Fort Lisa and Cabanne's Trading Post, both located in the city's far northside, were first occupied in the early 19th century. Landmarks from the mid-19th century include Culter's Park, or "Winter Quarters" located in Florence, and Fontenelle's Post located south of the city. Downtown has historical plaques marking the first building in Omaha and the first burial. The city has designated numerous landmarks in North Omaha, including the former town of Saratoga. South Omaha, Dundee and Benson also have numerous historical landmarks. Kountze Park was the site of the 1898 Trans-Mississippi Exposition. Fates of historic sites The oldest historic sites in Omaha are located in the Florence neighborhood. Other important sites include Capitol Hill, the site of Central High School, where the city's founders held a picnic on July 4, 1854, and Miller's Landing, where the Lone Tree Ferry brought settlers over from Iowa. There is a plaque commemorating Capitol Hill, and Miller's Landing was recently reclaimed and renovated by the city. Prospect Hill Cemetery, where many of the city's founders are buried, stands intact in North Omaha. One of the