The University of Washington Botanic Gardens dates back to 1934 with the opening of what is now the Washington Park Arboretum.  The Arboretum was originally laid out from a plan designed by the Olmsted Brothers landscape architecture firm, and is highlighted by the ¾ mile long Azalea Way and numerous taxonomic, ecogeographic and horticultural displays.  The Arboretum features one of the most diverse woody plant collections in temperate North America, and is located on 230 acres near downtown Seattle.  Since 1980, the UW Center for Urban Horticulture has offered an additional site and room for expanding facilities.  Combined, the UW Botanic Gardens contains 320 acres with over 4,500 taxa and 40,000 plants.  Other than the Japanese Garden, which is managed by the city of Seattle within the Arboretum, both sites are free to visit and open every day of the year from dawn to dusk.