Altgeld Hall and its 40-m-tall (130-foot) bell tower is a defining symbol of the University of Illinois Urbana-Champaign located in Urbana, Illinois, United States. Completed in 1897 in the Romanesque style, the historically significant tower consists of brick mass masonry walls and a sandstone exterior, with distinctive turrets at each corner. The upper portion of the tower is supported by the mass masonry wall below on two sides, and large transfer girders on the opposite sides. The tower's complex structural behavior is due to its geometry and proximity to the New Madrid Seismic Zone. An extensive restoration program is being completed to ensure the tower’s seismic and wind structural performance. Vertical, horizontal, and through-wall reinforcement was cored into the tower’s walls to strengthen the existing masonry and secured in place using cementitious compatible injected fill (CIF). The CIF was also used to fill internal voids in the masonry, especially at the interfaces between stone and brick. Limited space in the wall sections required careful coordination to install reinforcement, especially the vertical reinforcement, which continued for the entire height of the tower masonry. Extensive investigations prior to construction included flatjack, shear, and material testing. The CIF material was tested and customized to ensure compatibility with the historic masonry while providing the structural performance required to interact with new interior concrete and steel elements. Quality control measures over the multi-staged injection sequence, including surface penetrating radar, were performed throughout the project to confirm the efficacy of the grout injection and reinforcement position. The repair methodology implemented successfully strengthened the tower while maintaining its landmarked appearance.