In the 1880s, plans were conceived to build a new city hall on the grounds, and in 1888, the expo area was cleared. An architecture competition was held in early 1889. Apart from Nyrop, who won the competition, Vilhelm Dahlerup and Valdemar Koch were among the participating architects. The design of the city hall was greatly inspired by the Palazzo Pubblico in Siena, Italy, and the design of the square was accordingly modeled on the shell-shaped Piazza del Campo outside that building.