Both are a photo of Otto Frank's office building where the Secret Annex is located. The Annex consists of two parts, a front house and a back Annex. Otto Frank set up a branch of his brother's company called The Dutch Opekta Company. They sold pectin, a powder made from fruit extract and used to make jelly. The office building was located at 263 Prinsengracht in Amsterdam. Thick lace curtains protect the hiders from the neighbors' view of them during the day. Black-out paper is used at night when the lights inside the Annex are turned on.

In front of the door to the Annex Bep's father, Mr. Voskuijl, built a swinging bookcase to hide the entrance of the Annex. Because of the warehouse personnel and visitors to the company those in hiding have to keep quiet during office hours.
The furnished rooms of the Annex limit the movement of the hiders. In the evenings, on Saturday afternoon, and on Sunday the hiders can use the front part of the building. Though after a few break-ins the front spaces were no longer permissed to use. (Furniture of the Annex was confiscated by the Germans after the arrest of the hiders)