55. Koester House (1859)

Built by the city’s first physician, Dr. Theodore Koester, this is one of the city’s most impressive historic homes, with three stories, 15 rooms, and 18-inch limestone walls. This mid-19th-century house, constructed in the new Anglo-American vernacular, also included a kitchen, basement, dumbwaiter, and other architectural innovations for the period. Now, an office building.