In Star Trek Voyager's pilot episode "Caretaker", the crew of the Voyager is transferred to a holographic simulation of a farm. I could not find any information about the filming location of the farm scenes.
Where was that scene shot?
There doesn't seem to be any mention of the location anywhere, but using a little google-fu searching for film location farmhouses near LA, Paddison Farmhouse stands out as pretty darn close. The wrap-around porch, the green roof, the wooden decorations, the gazebo, the fence all look spot on. The Red barn(s) aren't spot on but are close and they may have been touched-up since 1995.
The scenes of the underground court on the Ocampa homeworld in the pilot episode "Caretaker" were filmed at the Los Angeles Convention Center. The scenes on the planet's surface, including the Kazon-Ogla village, were filmed at the El Mirage Dry Lake Bed in the High Desert of Southern California.