Mrs. Howlett has lived in the Algarve since 1989 and completed an identical feat two years ago to celebrate her 80th birthday.
The swim took place on 2 August at the Loulé Municipal swimming pool, a week after a successful practice run, and took around two hours.
Dorothy, who is is also a keen tennis player, undertook the swim for the building fund of the International Evangelical Church of the Algarve in Vale Judeu and proved once again that age is only a number.