Shimizu Lighthouse清水灯台EP 12025-05-27Based on the characters' range of movement in the show, and since a lighthouse also appears in the background of the rocket contest in Episode 5, the original is presumed to be this lighthouse. However, the terrain is completely different and it is not by the sea. Also, when the anime aired, the official side held a lighthouse-climbing event here, so the original can be confirmed to be here.
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