Of in place of interest indicates that interest is a property that pertains to the place. Similar constructions abound: a man of mystery, a tale of intrigue, a man of parts, a soldier of fortune.
In certain contexts a place famous for scenery or a famous historical site may be equivalent in meaning to place of interest, but place of interest is a much more general term. A place may be of interest for its culinary scene, its language, its current performing arts, and any number of other things.
Student or Learner