The building that was to be Anne's home for the next two years was her father's office building. The hiding place or the secret annex was located inside this building,the door to the right of the landing in the office led to the secret annex at the back of the house. No one would have suspected that there could be so many rooms behind that door from outside. The secret annex was located because no one could have guessed of its location as it did not seem to exist in the floor plan.