<P> In April 2011, it was announced that Ben Stiller had been cast in the lead role, though no director was attached . The following July, it was announced that Stiller was also due to direct the film . </P> <P> In January 2012, it was announced that Kristen Wiig would play the female lead, with Shirley MacLaine attached to play the mother of Ben Stiller's character . This was followed by reports in February that Patton Oswalt and Adam Scott joined the film . In April 2012, Kathryn Hahn was cast as Odessa, Walter's sister, and Josh Charles was cast as the ex-husband of Kristen Wiig's character, though he was replaced by Kai Lennox . Later that month, Sean Penn was cast in what was described as a "small but pivotal supporting role" as photojournalist Sean O'Connell . </P> <P> The portions of the film set in Nuuk, Greenland, were in fact shot in Stykkishólmur, a village on the Snæfellsnes peninsula in Iceland, and Höfn, a village in southeast Iceland . Later sequences set in Stykkishólmur were actually filmed in Seyðisfjörður . The sequences where Walter Mitty follows Sean to Afghanistan were also filmed in Iceland, at the Skogafoss waterfall and in Vatnajökull National Park . </P> <P> During the skateboarding scene in Central Park, skateboarding legend Rodney Mullen served as Ben Stiller's stunt double . </P>

What part of iceland was walter mitty filmed
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