After 40 years of operation, Northern Pacific's Queen Anne-style passenger depot, built in fall 1882, was showing its age. After a new depot was constructed in Bismarck, local business leaders lobbied Northern Pacific to replace Mandan's building. In June 1920, defective electrical wiring caused a major fire that destroyed the entire wooden second story, including offices used by Western Union and the yardmaster, roadmaster, and trainmaster. Temporary offices were established in spare cabooses parked on sidings. Because the railroad was losing money, it rebuilt the second floor with a plain design. After receiving a new coat of paint, the depot remained in service until 1929.
In 1928, chief engineer Howard Stevens proposed replacing the lunchroom and depot with three buildings in a brick Colonial design unlike any existing Northern Pacific depot in the country. Although the board of directors also considered a more traditional company design, it approved Stevens's proposal.
The Steen Company of Grand Forks built the current depot just north of the old one for $61,342 (about $1,150,000 in 2025 dollars). After its dedication in February 1930, the old depot and lunchroom were demolished and replaced by new tracks and a platform.
The one-story red-brick building is 34 feet wide and 156 feet long, including a 22-foot covered platform at the west end. Its original layout included a 32-by-30-foot general waiting room, a 13-by-26-foot women's restroom, an 11-by-17-foot smoking room, a 22-by-32-foot baggage room, a 32-by-30-foot express room, and restrooms. No basement was needed because steam heat initially came from the nearby engine-terminal power plant and later from a boiler in the basement of the Beanery, built west of the depot in 1928.
Columned porticoes at each main entrance establish the Colonial design. Open balustrades crown the porticoes, while arched transoms and flanking windows accent the depot entrances. A cupola and surrounding balustrade provide another Colonial feature. The lunchroom's arched windows and broad fireplace chimney complete the effect.
Only the depot and Beanery were built. Railway management moved offices intended for the third building into vacant second-floor space in the existing freight house. The freight house was remodeled during the 1970s and briefly served as a call center. It later housed the Morton Mandan Public Library on its main floor and a restaurant on the east side of its second floor.
After final passenger service ended in 1979, the buildings were transferred to the City of Mandan. The depot and Beanery were remodeled in 1992 and leased to area businesses. In 1995, the Fort Abraham Lincoln Foundation moved its administrative offices and the Five Nations Art Gallery into the depot. A German-style beer hall and restaurant opened there in September 2017, while the gallery moved next door into the smaller former Northern Pacific lunchroom. The depot reopened as an event center in 2021.