Onsala Space Observatory is located some 45 km south of Gothenburg and about 20 km from Kungsbacka. The visiting address is Observatorievägen 90, Råö, Onsala.
The Group for advanced receiver develoopment, GARD, is not located in Onsala but at Chalmers Campus Johanneberg in Gothenburg, in the same building as the Department of microtechnology and nanoscience, MC2:
The observatory area with restricted access (information and map).
Map of the observatory area:
The map above with better resolution: Map ObservatoryArea.pdf