Ladder Paradox is a medieval knight riding a charger carrying a lance in place of the ladder, but honestly any long horizontal object will do for this thought experiment. It involves a ladder, parallel to the ground, travelling horizontally and therefore undergoing a Lorentz length contraction. It is a famous thought experiment, which shows that why you can fit objects into spaces that are too small for them. And also why you can’t, depending on your perspective. On the other hand, from the point of view of an observer moving with the ladder, it is the garage that is moving.