Such dreams often recur. Dreamers dream of being in an environment they once knew. Sometimes, in the dream, the scenes in reality do not even feel like you have been there, but in the dream, they often appear.
Such dreams are often the transformation of certain experiences in childhood memories that left a deep impression on your subconscious. It may be some pleasant experiences of childhood, or it may be sad experiences, which depends on your emotions when dreaming about this environment.
If it is the former, in that environment you feel happy and physically and mentally relaxed, it is a reappearance of the pleasant experience of the body, and self-relaxation of the body. If it is the latter, it is a release from past anxiety. In either case, it is a favorable self-regulation of the body.
After falling asleep, people's response to some common stimuli around them becomes extremely slow. However, some weak stimuli that are not easy to detect during the day will turn into strong signals at this time, be transmitted to the cerebral cortex, and be strengthened in some active areas.
Such dreams are often signaled by the fine stimuli of some external environment during the day or when falling asleep, and are amplified in the dream, so they evoke an important memory buried in the subconscious.
In fact, in your consciousness, this memory may have been blurred or even forgotten. What appears in the dream is only the deformed shape after subconscious processing. Therefore, in the dream, you will feel that the environment, people, and things you dream of "appear to have met". I haven't been there, but I feel familiar; I don't know, but I think I've seen it somewhere.