Commuters returning to work after the Christmas break faced major delays combined with annual fare hikes this morning.
South West Trains and South Eastearn trains were among those suffering from major disruptions. National Rail said.
A broken down train at Twickenham added further chaos. Social media lit up with disrupted commuters, late in for their first day of work.
Jeremy Corbyn was at Kings Cross this morning protesting with campaign group Rail Rip Off following the 1.1% increase in regulated rail prices over the weekend.
He said it was absurd that parts of the railways in the UK were allowed to be owned by state-owned companies abroad, and called on the Department of Transport to step in and reverse the rise in rail fares.
Action for Rail, a group run by rail unions and the TUC, said their UK workers were spending 13% of their monthly wages on rail travel compared with 2% in Italy.
The analysis looked at a UK worker on an average salary who is spending 13% of their monthly wages on a £357.90 monthly season ticket from Chelmsford to London.
By contrast, the average amount of salary going on a monthly season ticket for a similar journey is 2% in Italy, 3% in Spain and 4% in Germany.
In France, which is the closest to the UK for cost, commuters still spend nearly a third less on season tickets than their counterparts in the UK, according to the research published by the campaign group.