According to Official Guinness Records,
The largest corkscrew is 1.73 m (5 ft 8.1 in) long, and was created by OK Watterfaescht (Switzerland) as measured in Watt, Switzerland, on 4 September 2015.The corkscrew was demonstrated to work on an outsized wine cork. It was created as part of the Watterfaescht festival held every 4 years.
For a complete list of 2015 records, please visit 2015 Guinness Records in Switzerland.