The Earliest Forms Of The Great Helms From The 12th Century Onwards Had By The 13th Century Proved To Be A Winning Design: The Flat Tops Of The Late 12th Century Helms Combined With The Reintroduction Of The Facemask Were Fairly Simple To Manufacture And Gave Excellent Protection. During The Early 13th Century Those Facial Protections Were Extended, So That Eventually The Extra Plates Covered The Back Of The Neck, Eventually Reaching The Shoulders And Thus Enveloping The Entire Head. The Great Helm Was Commonly Worn Over A Mail Coif And The Larger Models Sometimes Even Over A Skull Cap, Which Gave Its Wearer A Level Of Protection That Had Previously Been Unimaginable. Of Course The Downside Of Added Protection Was That The Visibility And Ease Of Breathing Were Substantially Worse Than With The Open Helmets Of Old. The Solid Surface Was Punctured Only By The Breaths And Narrow Eye Slits. As This Was A Time Of Fervent Crusading, Many Of These Helms Had As An Extra Protection (Both Physical And Spiritual) A Cross-Shaped Reinforcement On The Face. This Design Can Be Found For Example In A Helmet In The German Historical Museum In Berlin, On An Statue In The Church Of Santa Maria La Real In Olite, As Well As In The Illustrated Manuscripts Of The Codex Manesse, The Maziejowsky Bible And The Cantigas De Santa Maria. Despite Its Legendary Aesthetics And Symbolism, The Great Crusader Helm Was Not Used On The Battlefield For Very Long, As By 1350 It Was Slowly Replaced By The Bascinet. The Great Helm Did Stay In Use, However, In The Ever More Popular Sport Of The Joust Where Maximum Protection Was Highly Regarded.