Episode 6 of the HBO miniseries Band of Brothers takes place in the Ardennes Forest around the town of Bastogne, a setting filmed in an unconventional way. The harrowing events that transpire are seen through the eyes of U.S. Army combat medic Eugene Roe (Shane Taylor) who is tasked with treating the men of Easy Company during the famed Battle of the Bulge, ’s last-ditch offensive aimed at splitting the advancing Allied forces in two during the winter of 1944-45. The Belgian forest blanketed in snow may appear to be a typical set, but the winter scene actually employs a hidden trick.

Bastogne is a Belgian town perched atop a ridge in the Ardennes Forest. Known for its extensive forests and rough terrain, the Ardennes proved a challenging obstacle in what would become the largest and deadliest battle for the United States during World War II. To make matters worse, the area experienced one of the coldest winters on record during the Battle of the Bulge that included freezing rain, snow, and dense layers of fog. Recreating such a significant and unique environment was a major challenge for Band of Brothers. As such, the series came up with an innovative approach.

Related: Why Band Of Brothers' Bastogne Story Was The Show's Turning Point

Band Of Brothers Filmed The Battle Of The Bulge Indoors

Band of Brothers Bastogne

Band of Brothers episode 6, “Bastogne,” takes place in the elements, but the HBO miniseries actually filmed the winter scenes indoors. Due to a large tax break from the UK government, HBO filmed most of its miniseries at the Hatfield Aerodrome in southern England, an old aerospace factory had been converted into an 1100-acre backlot. The miniseries built some exterior sets at Hatfield while using the majority of the hangars to house costumes, props, weaponry, and other equipment; however, some hangars housed entire indoor sets like the massive one created for the Bastogne scenes in episode 6.

The dense forest was recreated indoors using real and artificial trees, the latter of which could be blown apart to simulate German shelling. Some artificial trees consisted of a fiberglass, hemp, and latex mixture while others were foam with a cardboard tubs core to keep them weighed down. Recreating the shelling was important as the Germans, at that time and location of the war, had timers on their mortar rounds that would explode in the treetops, raining down shrapnel and tree fragments onto the helpless soldiers below. For artificial snow, the production used an estimated third of a million pounds of paper blend that included cellulose, polymer, and plastic. This helped Band of Brothers recreate the Battle of the Bulge indoors.

How CGI Enhanced Band Of Brothers' Bastogne Scenes

Shane Taylor as Eugene Roe and Lucie Jeanne as Renée Lemaire in Band of Brothers Bastogne

The miniseries prides itself on authenticity, meaning practical effects and real props and equipment are employed wherever possible. However, Computer-Generated Imagery (CGI) is used in episode 6 for one of the excursions outside the Ardennes to depict an airborne resupply to the besieged troops at Bastogne. The CG parachutes and C-47 planes are tracked into a shot of the battered town. It’s a relatively minor effect when considering the breadth of the battlefield depicted, but it adds a layer of reality that, without CGI, may have impacted the Bastogne scenes.

It wasn’t just the Band of Brothers crew who had their work cut out for them in recreating the Ardennes Forest indoors. On top of portraying paralyzing fear in the face of death, the actors were tasked with conveying the body-numbing chills of freezing temperatures and soggy snow while actually treading through paper shreds inside an airplane hangar. In the end, the actors and crew did an effective job in recreating the snowy battlefields of the Ardennes, even though the real event was more extreme than anything that could be replicated on screen.