Undertaken between 1978 and 1983, the plaza, considered Vancouver’s civic core and primary public space, was designed by Cornelia Hahn Oberlander and Arthur Erickson as a continuous roof garden with a mix of enclosed and open spaces. Conceptualized as an urban oasis, the roof garden extends three blocks from the Erickson-designed Law Courts Building to the Vancouver Art Gallery, blending structure with landscape as it traverses various levels through a complex of at-grade and underground civic buildings. An early example of the integration of green-roof technology, the entirety of the multi-level plaza is sited on the adjoining rooftops of different buildings. Minor alterations were made to the original design to accommodate public events associated with the 2010 Winter Olympic Games.
Designing for a variety of sensory experiences and activities, Oberlander intentionally sequenced spaces and materials throughout the linear park. Paved in concrete and pink granite, the plaza is filled with a repeating selection of plantings chosen by Oberlander for their massing qualities, texture, and seasonal variation. Built to appear as hanging gardens, rows of elevated planters overflowing with rose and laurel accent building façades and line a series of terraces. Tucked between the terraces, waterfalls cascade past office windows and skylights into reflecting pools to drown out street noise. On top of the courts building, lush beds of rhododendron, pine, bearberry (kinnikinnick), and ivy border secluded gardens and paved open areas. The uppermost roof gardens connect to the street level via a series of stair-ramps, or “stramps,” flanked by box planters of lodgepole pines, magnolia, and maple. At grade level, a twenty-five-foot-high grass mound topped by pines, maples, photinia, and rhododendron curves towards a sunken plaza. Containing twin ice rinks under glass domes on either end, the plaza passes under a pedestrian-only section of Robson Street, returning to grade in front of the Vancouver Art Gallery. Sculptures including Spring by Alan Chung Hung and Primary No. 9 by Michael Banwell are scattered throughout the plaza. Closely spaced maple tree allées interspersed with planting beds create a continuous canopy over adjacent streets.