Birmingham City Council says the St Chad's and Queensway tunnels will be shut from 10pm on Friday 18th July until 6am on Monday 1st September.
Before the tunnels are closed completely there will be two weeks of overnight closures, running until the 18th July. These will run from 10pm to 6am.
After the tunnels are reopened there will be another four weeks of overnight closures.
The closures mark the second wave of refurbishment of the tunnels which started last summer. The tunnels are 40-years-old and had never been refurbished until last summer.
There is more information on the closures on the Brum Tunnels website.
- Between 75,000 to 85,000 vehicles a day use the route
- St Chad's tunnel is 170 metres long and the Queensway tunnel is 545 metres long
- More than 200,000 additional journeys were made on public transport during last summer's closures
- Around 120 people will be working in the tunnels at any one time and works will be taking place 24 hours-a-day