The Old Bushmills Distillery claims and is considered to be the oldest licensed distillery in the world. A licence to distil in the area was granted to Sir Thomas Phillipps in 1608 by King James I  and the 1608 date is printed on the labels of the Bushmills brand.

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In 2008, Bushmills celebrated the 400th anniversary of the original licence to distil by releasing a limited edition of Irish whiskey with exceptional smoothness called Bushmills1608. Since 2005, the company has been owned by Diageo one of the world’s leading premier drinks businesses.
Tours are offered giving a unique insight into the knowledge expertise involved in the whiskey making process. Bookable in advance for groups. Requests for some other languages can be arranged with tour guides. Formal tour lasts 45-60mins ending with a whiskey tasting.
Children under 8 are welcome to visit the distillery but are not permitted on the tours. The tour is not suitable for persons with walking difficulties or wheelchair users.

Sourced from:
http://www.discovernorthernireland.com/Bushmills-Distillery-Bushmills-P1635
http://www.irishtourist.com/details/old_bushmills_distillery.shtml
http://www.bushmills.com/
http://en.wikipedia.org/wiki/Old_Bushmills_Distillery