Operators at a 9-9-9 centre in Blackburn have helped celebrate the service's 75th birthday today.
They work in BT's oldest current emergency call centre.
Burnley, Livepool, Macclesfield, Manchester and Rochdale, were among the first areas outside London to use the treble nine number.
Emergency call service 999 is turning 75. Blackburn has the oldest of BT's current centres, it's been going for 50 years handling more than 7mi calls a year and employs more than 140 people.
Burnley, Liverpool, Macclesfield, Manchester and Rochdale were among the first areas outside London to introduce the 999 service.