Washington Park holds two of Portland's most visited attractions: the Japanese Garden (5.5 acres, widely considered the most authentic outside Japan) and the International Rose Test Garden (free, 10,000 plants, views over the city to Mount Hood). Powell's City of Books on West Burnside takes up an entire block and stocks over a million new and used titles — the free map is useful. Forest Park, the largest urban forest park in the US, has 80 km of trails beginning just minutes from downtown. Pioneer Courthouse Square is the civic heart of the city, surrounded by transit lines and flanked by the 1869 Pioneer Courthouse. Council Crest Park at the top of the west hills gives panoramic views of four volcanic peaks on a clear day.