Osaka Castle, which stands in the heart of Osaka City, western Japan, is surrounded by a park covering more than 100 hectares. Each year, over 2.7 million people visit this urban park famous for its castle, gardens and multipurpose hall. This green oasis is open 24 hours a day, so people come here around the clock. For some, it is a place to do exercise; for others, a place to relax or sightsee. For 3 days, we asked visitors what makes the Osaka Castle Park special and why it holds a place in their hearts.