The disruption to London's transport network caused by snow and freezing temperatures has begun to ease.
Heathrow Airport's second runway has reopened after four days and it is hoped two-thirds of flights will operate on Wednesday.
Eurostar said it hoped to run 43 services out of the usual 52 after two days of severe disruption and delays.
And trains are running again on the East Coast mainline which was suspended on Tuesday when power lines came down.
Most train services are back to normal but there could be disruption on First Capital Connect, First Great Western, London Midland, National Express East Anglia and Virgin Trains.
There is no service between Stratford and Stansted Airport and Stansted Express is running a revised service.
Thousands of passengers were left stranded at Heathrow Airport when heavy snow fell on Saturday.
The southern runway reopened at 1700 GMT on Tuesday but travellers have been warned it will take some time before the full schedule is fully restored.
Passengers are urged to check on online for a list of flights that are due to operate and not to travel to the airport unless the departure is confirmed.
A statement on the airport's website said: "We are now working with airlines to return to a normal schedule as quickly as possible.
"We are truly sorry for the disruption the weather is causing to our passengers. We are doing everything we can to get you on your journey."
East coast railways said it would operate a near-normal service but journeys north from London would take an extra 15 minutes after damage to overhead power lines near Huntingdon.
Some trains between King's Cross and Leeds have also been cancelled.
East Coast managing director Karen Boswell said: "We appreciate that many people are travelling home for Christmas over the next few days and our staff are working as hard as possible to ensure our passengers arrive at their final destination with minimal disruption."
Eurostar also said it would run a near-normal timetable and revert to checking-on passengers for the service they were booked on.
About 100 people slept in the St Pancras terminal building on Monday night and hundreds more joined the queue on Tuesday, braving freezing temperatures for several hours.