There are six landmark architectures in the Kakioka Magnetic Observatory. The characteristics of these buildings are as follows:(1) The variation building is a semi-underground granite building that has two advantages: one is stability at room temperature in the basement, and the other is low humidity in the room above ground.(2) The thick walls of the magnetic laboratory, the new variation building, and the new absolute building are made of unusual white brick. (3) The ornamentation found on the facade of the magnetic laboratory, the office building, and the electrometer hut show influence from the building design trends of the era, and the office building is one of the first examples of Spanish detail implementation in modern Japan.