ViggsöMany of the islands in the archipelago have fascinating histories. There’s Kymmendö, where Swedish playwright August Strindberg summered until he upset the locals by writing about them, and there’s Ytterby, where several rare minerals were discovered. The claim to fame of Viggsö is that it's where members of the Swedish supergroup Abba wrote many of their most famous songs. Today Abba is a worldwide phenomenon thanks to the musical Mamma Mia! but in their home country their popularity has never dimmed since they first emerged in the 1970s.