Chicago, IL: Union Station in Chicago, completed in 1925, was built jointly by the Pennsylvania, Burlington, and St. Paul Systems. This station also is used by the trains of the Chicago and Alton Railroad. Its design includes many new features and improvements-the best of everything that has been developed by architectural and engineeering science for comfort and efficientcy in handling a vast passenger traffic. The construction of this station, with its approach tracks practially through the heart of Chicago, involved difficulties in some respects greater then those ever before incountered in a similar undertaking.