The South Dakota State Capitol is the state capitol building of the U.S. state of South Dakota. Housing the South Dakota State Legislature, it is located in the state capitol of Pierre at 500 East Capitol Avenue. The building houses the offices of most state officials, including the Governor of South Dakota. Construction The building was constructed between 1905 and 1910. The designs for the building were executed by the Minneapolis architectural firm of Bell & Detweiler, who gave the building similar features to the Montana State Capitol in Helena, Montana. The planning and construction cost was almost $1 million. In 1921 plans began for a large addition located on the building's north side. The Capitol Annex was designed by architect Bell's later firm, Bell & Kinports. Construction costs were estimated at $500,000. Construction drawings were issued in 1931, and the Annex project was completed in 1932. Features The floor in the capitol building is made of terrazzo tile. Common lore says the floor was laid by 66 Italian artists. To give these artists a chance to place a mark in the building (without allowing them to actually sign their names to the floor), each is said to have been given a blue stone to place in the floor. Only 55 of these tiles have been found, however. It is thought that the remaining stones may have been placed in locations now covered by walls, doors, or carpeting. From the first floor, a marble staircase leads upstairs. In front of the staircase, display cases house the First Lady Gown Collection. Miniature replicas have been made of the gown worn by each first lady to the state inaugural ball. These replicas are worn by dolls in the display case. Along with the doll, a picture of each governor's family and other mementos are also displayed. On the second floor, the marble staircase leads into a rotunda. The dome of the rotunda is 96 feet high. The bottom ring is designed to resemble a string of ribbons joined together, which is meant to symbolize the eternal nature of government. The 3rd pillar from the top on the right side of the railing is upside down due to a mistake during construction of the staircase. The interior of the dome is decorated with sixteen images of the Tree of Life. The dome also displays acanthus leaves to represent wisdom and a pasque flower,