If you want to keep the kids entertained all day long, head to Seattle Center. This 74-acre cultural center and amusement park stands on the northern edge of downtown at the end of the monorail line. The most visible building at the center is the Space Needle, which provides an outstanding panorama of the city from its observation deck. However, of much more interest to children are the Children's Museum and the Seattle Children's Theatre. This is also Seattle's main festival site, and in the summer months hardly a weekend goes by without some special event filling its grounds. On hot summer days, the International Fountain is a great place for kids to keep cool (bring a change of clothes). In 2012, Seattle Center will celebrate the 50th anniversary of the Seattle World's Fair.