Sweden was claimed to be the location of Atlantis by Olaus (Olaf) Rudbeck in the 17th century. Before him another Swede, Johannes Bureus, expressed similar views. His friend Carl Lundius supported Rudbeck’s theories, but received none of the acclaim.
The discovery of the Mid Atlantic Ridge led René Malaise and Hans Pettersson to suggest the Azores as remnants of Atlantis, an idea still popular today. Around the same time Gunnar Rudberg proposed that Syracuse in Sicily had inspired some of Plato’s description of Atlantis.
More recently, we seem to have come full circle as Bertil Falk has revived some of Rudbeck’s ideas(a) and a short illustrated 2007 paper (updated 2015)(b) by Robert Fritzius also added some additional modern support. However, for something quite different we have Carl Festin promoting a Mediterranean location.
*(b) http://www.datasync.com/~rsf1/vel/atlantis.htm (offline Feb. 2018)*