The Gallery in the Forest, once the old sawmill, houses many other exhibits, and the Theatre in the Forest holds concerts and performances on weekends in the summer.
Many famous musicians have performed in the Theatre of the Forest. 
mnli hypothesis: Many famous musicians have performed in the Theatre of the Forest.  premise: The Gallery in the Forest, once the old sawmill, houses many other exhibits, and the Theatre in the Forest holds concerts and performances on weekends in the summer.