The long-awaited nocturnal London Underground service will begin this week after more than a year of delays and discussion over pay and conditions for staff. Here is everything you need to know.

When is the launch date?

The Night Tube, which will offer a 24-hour service on Fridays and Saturdays, will begin on Friday 19 August.

Which lines will run all night?

The service will launch on the Central and Victoria lines this Friday, followed by the Jubilee, Northern and Piccadilly lines in the autumn.

How often will trains run?

On the Victoria and Jubilee lines, trains will run approximately every 10 minutes across the entire lines.

The Night Tube service will launch on Friday 19 August iStock

On the Central line, trains will run every 10 minutes between White City and Leytonstone. They will run every 20 minutes between Ealing Broadway to White City and Leytonstone to Loughton and Hainault.

No service will run between North Acton and West Ruislip, Loughton and Epping and Woodford and Hainault.

On the Piccadilly, trains will run every 10 minutes between Cockfosters and Heathrow Terminal 5, but there is no service on the Terminal 4 loop. There is no service between Acton Town and Uxbridge.

On the Northern line, trains will run every eight minutes between Morden and Camden Town. They will run every 15 minutes from Camden Town to High Barnet and Edgware.

There is no Night Tube service on the Bank and Mill Hill East branches.

Night Tube map
Night Tube service map TfL

Will it be more expensive than normal tickets?

No, fare will be the same as standard off-peak fares. Day travelcards are valid on the day of issue and for journeys starting before 4.30am the following day.

For example, if you buy a day travelcard at 11am on Friday, you can use it until 4.29am on the Saturday. As usual, capping on oyster cards or contactless cards still applies.

Will the night tube be safe?

Around 100 additional police officers will be deployed to protect staff and commuters on the Night Tube, after London Mayor Said Khan committed £3.4m in funding. The British Transport Police will patrol the 144 stations open 24-hours each weekend when the new service begins, as well as BTP community support officers.

How will the new service benefit London?

A report for the independent body London First estimated that the night tube would be directly responsible for more than 2,000 new jobs, including 500 extra on the service itself. The study also suggested the service could boost London's economy by £77m annually, with London's overall night-time economy worth £30bn a year by 2030.

According to TfL, the new service will cut night-time journeys by an average of 20 minutes, but some will be reduced by more than an hour. The Night Tube will accompany TfL's system of night buses, of which usage has risen by 173% since 2000.