McLennan Library Building, Brutalist library building in Ville-Marie, Canada.

McLennan Library Building is a structure constructed from prefabricated concrete panels joined together with a reinforced concrete skeleton. The interior is defined by a central stairwell and elevator core that organizes vertical circulation throughout all floors.

The building was constructed on land formerly occupied by a mansion that served as a training center for Canadian military officers during World War I. This shift from private residence to public educational facility marks a significant change in how the site has been used over the past century.

The building is named after Isabella McLennan, whose large donation to McGill funded the purchase of books. The fourth floor holds Rare Books and Special Collections, begun in the 1850s, with strengths in Canadiana, David Hume and 18th-century English and French literature, including the circle of Fanny Burney. The sixth floor houses the McGill University Archives.

The main entrance sits at the south end of the concrete terrace, because the Redpath entrance was closed after the terrace renovations finished in January 2014 for lack of funding. A bridge walkway links McLennan to the Redpath Library Building. Inside, all movement between floors goes through the central stairwell and elevator core.

The sixth floor holds the McLennan Tranquility Zone, funded by the Arts Undergraduate Improvement Fund, with reclining lounge chairs, square side tables, exercise balls and a central Zen Garden. The Spin Bike Garden on the first-floor group study area has two silent spin bikes surrounded by plants and meditative art.