Dublin, July 1 (IANS): DJ Calvin Harris took his girlfriend and singer Taylor Swift to the Guinness factory after her concert here.

According to a source, the duo, who were earlier announced as the world's highest paid celebrity couple, were spotted taking a tour around the tourist attraction on Tuesday learning how the Black Stuff is made, reports femalefirst.co.uk.

“Taylor loves an impromptu trip, especially in a city she's not overly familiar with. They managed to keep themselves low profile so they weren't bothered by fans,” The Sun newspaper quoted the source as saying.

“They looked to be really enjoying themselves surrounded by all that alcohol,” the source added.

Swift and Harris have been able to see a lot of each other this week as they enjoyed a double date with her former boyfriend Joe Jonas on Sunday.

The "Shake it off" hitmaker and Harris were joined by Jonas and his rumoured girlfriend, 20-year-old model Gigi Hadid, for a boat trip on the River Thames in London.