More than 100,000 rugby fans are expected in Cardiff on Saturday as the two unbeaten sides in this year’s Six Nations clash.
The Wales v England game at the Principality Stadium is a 72,000 sell-out, with many others set to watch the match in the city.
There will be a full city centre road closure between 13:15 GMT and 19:45, with kick off at 16:45.
Supporters have been warned to travel early and plan journeys.
It will be the first international match in the city since Severn Bridge tolls were abolished, but the M4 into south Wales is still expected to be congested.
Scott Road and Park Street in Cardiff city centre will be closed early to prepare stadium gates.
From 13:45, other roads including Duke Street, Castle Street, High Street, St Mary Street, Caroline Street, Wood Street and Westgate Street will be shut in their entirety.
While there are no planned engineering works, trains bringing fans from London and the south Wales valleys are expected to be busy, with fans warned to travel early.
Queen Street station will close at 18:00, with a post-match queuing system in place at Cardiff Central.
Buses will also be diverted out of the city centre from 13:15 to 20:00, with stops moving to Churchill Way for the east, Greyfriars Road for the north and Tudor Street for the west.