 If the assembly in public is expected to involve more than one participant, its organisers are obliged to notify executive or local self-government authorities of the upcoming event few days in advance in writing.However, legislation does not foresee an authorisation procedure, hence the authorities have no right to prohibit an assembly or change its place unless it threatens the security of participants or is planned to take place near hazardous facilities, important railways, viaducts, pipelines, high voltage electric power lines, prisons, courts, presidential residences or in the border control zone.The right to gather can also be restricted in close proximity of cultural and historical monuments.