The official Olympic train service will depart from Kent for the first time this morning.
Kent's high speed services are being used to take hundreds of thousands of passengers from St Pancras to the Olympic park.
But for thousands in Kent it means they will lose regular high speed services to London.
Southeastern say they'll put on extra carriages on slower trains to the capital.
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Tuesday afternoon's weather for the east of the region
Tuesday afternoon's weather for the west of the region
Tuesday's weather for the east of the region