Freestanding structures built to commemorate, mark or memorialize rather than to be occupied day to day: the monument, the pyramid as a monumental tomb form, the mausoleum, and the freestanding tower not itself a tall commercial building, such as a bell tower, minaret or observation tower raised as a landmark. Belongs here: any named structure whose primary purpose is commemorative, monumental or landmark-marking rather than habitation, worship or work. Does not belong here: a tower that is itself a tall commercial or residential building, grouped under tall buildings and skyscrapers, or a mausoleum that is also the primary building of an active religious site, which belongs under religious and sacred buildings if worship rather than commemoration is its primary living function.