Tivoli is the second oldest amusement park in the world. It opened in 1843.
With 4.033 million visitors in 2012, Tivoli is the second most popular seasonal theme park in the world, the most visited theme park in Scandinavia and the fourth most visited in Europe, only behind Disneyland Paris, Europa-Park Rust and the Efteling.
And if you are wondering the oldest amusement park is also in Copenhagen. It's Dyrehavsbakken near the Deer Park.