Djurgården is an island located in Stockholm, Sweden. It is a popular tourist destination, with many parks, including the Royal National City Park, which is the world's first national city park. I would recommend to either take the SL boat (public ferry) to Blockhusudden and then walk your way back the shore to Gröna Lund or the other way around. It`s a great walk and you can stop at some venues for a coffee or a drink. It is also home to attractions such as the Vasa Museum, Skansen open-air museum, Gröna Lund amusement park, and the ABBA Museum.