When exactly was the Gustov Line broken? A lot of websites say " over a 4 day perios." Could someone please help me find the actual date. Thanks

4 answers

http://www.ibiblio.org/pub/academic/history/marshall/military/wwii/50.years.ago/jbd/may1944.txt
Scroll down to May 16. Does that help?

??
This site discusses the battle for the Gustav (note spelling) Line in detail. The Allies started the attack on May 11. You can read the details and figure out when the Line was officially broken.

http://www.nzetc.org/tm/scholarly/tei-WH2-2Ita-c1-3.html#name-006486-1
I don't see when it ended :S
Monte Casino was captured on May 18 -- so the battle took place between May 11 and May 18. Battles often take several days -- with fighting back and forth -- before one side captures the territory.