Hyouka Episodes 4 to 5 features the characters going to what is pretty much a fictional Chitanda residence in the agricultural area east of the urban area of Takayama. Note: While I cannot pinpoint the estimated location of her house, those familiar with the topography of the Japanese Alps will be able to do so *hint hint*.
The only clue that gives away the direction of travel is that, Oreki and Satoshi meet by the river in central Takayama, then head east past this creek.
All anime images are from Kyoto Animation, fair use for educational purposes.
The open areas really gave KyoAni creative freedom in landscaping the backdrops, with real-life locations thrown in. For example, the Torii gate in the background belongs to Suwa Shrine, but the small road that Oreki and Satoshi are walking along does not exist in real life.
Roadside Screenshots courtesy of Google Streetview, fair use for educational purposes.
Scenes such as this may have been creatively inspired by real-world locations surrounding Suwa Shrine.
Going back to town, the Hida High School plaque at the entrance.
The exact postbox in which Oreki airmails a letter to his manipulative older sister.