Union Trust Building

A fourteen-story steel-framed tower faced in buff brick and terra cotta, built on a U-shaped plan whose two end pavilions flank a recessed central bay over a light court. Tall brick piers run nearly unbroken up the shaft and gather into round-arched windows with slender colonnettes at the top floor. The crowning cornice is a dense band of Sullivanesque terra cotta — interlaced foliage, spirals, and seed-pod forms — punctuated by projecting lion heads at the corners, with oval windows set into the upper stories. The lowest two floors are a later, plainer remodeling, stripped of the building's original ornamented base. A bracketed corner clock reads "705 Olive / Hotel Saint Louis."

Adler & Sullivan designed the Union Trust Building in 1892-1893 for the Union Trust Company, immediately after the firm's nearby Wainwright Building. Louis Sullivan led the design and Dankmar Adler the engineering of the fourteen-story steel-framed tower, laid out on a U-shaped plan around a central light court. Its street level originally carried an elaborate buff terra-cotta base — a broad entrance arch, large circular windows, and giant heraldic lions bearing monogrammed shields — but that ground-floor design was stripped in a remodeling between 1924 and 1929, leaving the ornamented upper stories and cornice intact. The building was listed on the National Register of Historic Places in 1982. Long used as offices and later known as the 705 Olive Building, it was rehabilitated in a roughly $55 million project and opened as the Hotel Saint Louis in 2019.