Campo Marzo, Public park in Vicenza, Italy.

Campo Marzo is a large public park near Vicenza's railway station, laid out with paved walkways, planted areas, and open green spaces for walking. The grounds feature multiple entry points, benches, and water fountains distributed throughout.

The area was already used for burials before Roman times; 17th-century excavations found cinerary urns and bronze idols. A 1074 deed records 80 walled fields bordered by ditches and the Retrone, used as pasture. The 1264 statutes mention public executions here, and in sieges the land could be flooded to reinforce the walls. In 1612 a "castello di terra" was built for exercises, the first attested military use.

The name is disputed: a 2019 survey by Rete Veneta and Liberi Pensatori found 70% of Vicenza residents say Campo Marzio and 30% Campo Marzo. Medieval fairs were held on Saint Felix's day (14 August) and Saint Gall's (16 October), attended by Venetians buying goods to ship to Venice by river.

The park lies just beyond the historic centre, against the railway line and at the foot of Monte Berico, about 600 m from Vicenza station. A straight avenue laid out from 1702 runs from Porta Castello across the former meadow to the Retrone river, giving a clear line to follow through the grounds.

In 2019 a poll by Rete Veneta and the Liberi Pensatori association found that 70% of Vicenza residents call the area Campo Marzio and 30% Campo Marzo. The dispute revived through Luciano Parolin's research on some 650 documents from the city archives, presented that year.