Where is for a place. In which works for a place too, and it is the safer pick when the noun is not a location. The town where she grew up. The study in which they measured growth. Relative pronouns as a set are in relative pronouns.
Is it a location?
A city, a room, a campus: where is fine. A situation, an experiment, a book, a year: where is usually wrong. The year where the score jumped should be when or in which. The method where they mixed the samples should be in which.
Time versus place is in when versus where. People versus things is in who versus which. Extra information versus needed information is in which versus that.
The bottom line
Real place: where can work. Everything else: try in which or when.
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