A particle therapy system that includes at least one irradiation chamber, in which an object is irradiated with a treatment beam, an antechamber, which is screened off from radiation occurring in the irradiation chamber and from which access is made to the irradiation chamber, and an access area, which leads to the irradiation chamber and connects the irradiation chamber to the antechamber, is provided. A support for a patient moves along a path of travel from the antechamber, through the access area, to the irradiation chamber. A radiation protection door is arranged in the access area, and the access area is configured geometrically in such a way that the path of travel in the access area is substantially rectilinear.
