 In June 2007 , they shot the bridge battle near Bovec in the Soča Valley , Slovenia . The location was chosen for its resemblance to New Zealand . A large bridge was built , which was modelled on the one Julius Caesar built to cross the Rhine . Whereas Caesar supposedly built his bridge in ten days , the filmmakers had around forty . The schedule was short though , but the authorities would only allow them this build time to not completely disrupt normal summer activities on the lake . The filmmakers made a trench to change the river 's course , so they could deepen the drained sides of the riverbed so it looked like one could drown in it . The crew also cut down 100 trees for shots of the Telmarines building the bridge ; the trees were moved to another side of the river for decoration . The bridge stood for two months before being dismantled . As part of the clean @-@ up , the cut @-@ down trees and parts of the bridge were sent to a recycling plant , while other portions of the bridge were sent to the studio for close @-@ ups shot against bluescreen . 
