Figure 5.2.25 – Gate escape devices require high maintenance to avoid them becoming entry points to the fenced area. A: One-way double gate escape device which is kept open due to the lack of maintenance. Vegetation growth or rocks or sand can leave the doors permanently open (Photo by: Minuartia); B: One-way for ungulates installed on Swedish roads (Photo by: M. Lindkvist); C: One-way single door escape device in a motorway provided by appropriate maintenance (Photo by: Cerema Ouest – JF Bretaud).