A stretch of motorway in Berkshire has been shut to allow a bridge to be demolished.
The M4 will remain closed both ways between junctions five (Langley) and six (Slough/Windsor) until 06:00 BST on Monday.
Highways England has warned of delays, with drivers being diverted via the A4 and A355 through Langley and Slough.
It is the first of 11 bridges to be demolished on the motorway which is being upgraded to a smart motorway.
The bridges are being taken down because they are not long enough to accommodate the new four-lane smart motorway.
The 32-mile section of the M4 between London and Theale in Berkshire is being upgraded by Highways England.
Work on the £862.4m upgrade began just over a year ago.