Rockefeller Hall, a gift from John D. Rockefeller, was completed in 1904. "Rock" is Bryn Mawr's largest residence and houses the College's architectural drafting studio. Rockefeller is most easily identified by its castle-like towers and arch, much like Pembroke Hall. Common to Bryn Mawr's earliest buildings, many Rockefeller rooms contain the original fireplaces and window seats. One of Rock's most popular and unique features is the leaded glass in the doors of its bedroom spaces. Since students are permitted to decorate the glass (with water-based paint), the hallways become virtual art galleries.