Battle of Hrtgen Forest lasted longer than Battle of Pusan Perimeter.
The Battle of Hrtgen Forest (German: "Schlacht im Hrtgenwald" ) was a series of fierce battles fought from 19 September to 16 December 1944 between American and German forces on the Western Front during World War II in the Hrtgen Forest about 50 mi2 east of the BelgianGerman border. 
The Battle of Pusan Perimeter was a large-scale battle between United Nations and North Korean forces lasting from August 4 to September 18, 1950. 
