The History Museum’s exhibition “Freemasons. 250 years of freemasonry in Estonia.” in the Great Guild building was put together to introduce the history of one of the oldest secular organizations with the largest membership in the world. The aim was to allow visitors to get to know the exciting spiritual and material world of the Freemasons to understand their modern goals and the role of the fraternity members in Estonian cultural history. A couple of hundred years old, the rare display items belonging to the museum's collection had not reached the public until this exhibition. The exposition, built on the principle of space within space, was designed as one of the leitmotifs of a masonic lodge. This form represents a 33-step staircase, amplified by a light graphic and sound background for a thought-provoking experience. The exhibition was created as a result of a joint project of Identity and Ruumilabor.