For me,the hardest dungeon in the entire Legend of Zelda series was the last dungeon,that is,Death Mountain,in the original Legend of Zelda for the Nintendo Entertainment System.You got Wizrobes shooting at you,lots of hard and new monsters/traps,and not to mention the oh so difficult Ganon. When I went through the dungeon the first time,I didn't have the Silver Arrows that were necessary to defeat him. I went back and got those right away,then I went to Death Mountain.I avoided all the traps and mobs (the Wizrobes were the hardest,as they kept on making me start over),but eventually I got to Ganon. After shooting several Silver Arrows,I finally killed the guy and rescued Zelda. I did this on a warm day in July,and I was going through the game in one entire sitting (my save feature wouldn't work.)When that music at the end played,I said to myself,"You are one committed gut to beat a Zelda game on one sitting". But I competed the hardest video game level in my life,and I was proud of myself.