In 1970 in Stockholm, Sweden, a project plan was formulated to build a subway station in Kungsträdgården. According to the plan, the building of the ticket hall and entrance would require that the 13 elm trees growing in Kungsträdgården had to be cut down.
This plan was met with massive protests by the inhabitants of Stockholm (and elsewhere) and included land occupation, formal appeals to the plan, protest meetings, marches, a press campaign and petitions.
The culmination of the protest was on the night between the 12th and 13th of May in 1971 when workers arrived to cut down the trees. A large police force (including mounted police) were there to protect the workers. However, due to the number of people present, the police judged that it was not safe to cut down the trees and the protesters had thus succeeded in protecting the 13 elms.
The elm trees are still standing in Kungsträdgården, although a scar caused by a chainsaw can be seen on one of the trees. (1, 2, 3)