Rail passengers have faced disruption throughout the day after Network Rail engineering works overran.
South Western Railway services to and from London Waterloo, the UK's busiest station, did not run until 10:00 GMT.
Evening commuters faced continued delays and cancellations. South Western Railway has said it aims to run a normal service on Tuesday.
Southern services between East Croydon and Victoria were also hit by disruption from the over-running works.
No trains were able to use the line between Waterloo and Surbiton until mid-morning, leaving trains and crews in the wrong place for the remainder of the day.
Network Rail has apologised to passengers.
On social media, passenger Silvia Mendes blasted the chaos as "a complete and utter shambles", with another suggesting "critical jobs" such as teachers, doctors and nurses had been affected.
A Department for Transport spokesman said: "The disruption is unacceptable, and we are seeking an urgent explanation from Network Rail as to why their engineering works have overrun."
Ashley Trim, who lives in Clapham, was travelling from Clapham Junction to work at John Lewis HQ in Bracknell this morning.
He said: "I have got a stockpile of compensation claims in my house because it's happening so much."
Matthew Smith's train from Portsmouth to London was cancelled, so he was forced to take a National Express coach.
Mr Smith said: "For the last five weeks, I have experienced delays or cancellations by up to 45 minutes every day. There is always some issue on the network."
As the evening rush approached, more frustrated passengers took to social media.
Sacha Kemp said: "The fun continues. Not only did you excel this morning @SW_Help & it took me 3 hrs to get to London but still not sorted for way home."
Other people have also had their say:
@SW_Help the information you are providing to passengers is embarrassing. Your staff say a train coming any minute and still here 50mins later...it’s not possible to screw it up this badly is it??— Big Ladder Photographer (@bigladderdrone) November 19, 2018
If being delayed by over 2 hours this morning wasn’t enough, only making it into office at 1, having to stay late to make up hours and just seen the train home is cancelled! @SW_Help— Simon (@surrey_gr) November 19, 2018
Network Rail said overnight work near Hampton Court was originally due to finish at 04:30 GMT but overran, hitting the morning rush hour.
The work was completed at about 10:00 and services began running - but on a widely disrupted timetable.
Data published by rail information website trains.im showed that at 10:45, 269 SWR trains were cancelled or more than 30 minutes late, equivalent to 75% of all services.
All lines and stations that were closed, including Woking, Surbiton, Raynes Park and Earlsfield, have since reopened.
However, trains across the whole Gatwick Express, Southern and Thameslink network may still be delayed, cancelled or revised.
The rail operator said disruption would continue until the end of the day.
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Passengers using SWR services were initially advised not to travel amid widespread cancellations.
A Network Rail spokesman said: "We would like to apologise for the disruption to passengers' journeys on South Western this morning.
"This was due to over-running engineering works in the Hampton Court area."
A long-running dispute over the role of guards on trains has previously crippled SWR services because of strikes.
SWR operates from London Waterloo to Berkshire, Surrey, Hampshire, Dorset, Devon, Somerset and Wiltshire.
The Rail, Maritime and Transport (RMT) union called for the resignation of Transport Secretary Chris Grayling after what it called the latest railway "meltdown".
General secretary Mick Cash said: "While the crisis on our railways deepens, the Transport Secretary Chris Grayling is markedly absent... He should go, and he should go now."
Lib Dem MP Ed Davey, who represents Kingston and Surbiton, tweeted: "Commuters will be extremely angry today that, after 18 months of appalling services, stations are shut and trains cancelled due to Network Rail failing to do engineering works on time. When will Grayling act?!"
Tooting's Labour MP Dr Rosena Allin-Khan said the response to the morning disruption was "not good enough".
Teachers are late, nurses can’t get in, people have jobs to go to, it’s unconditional. It’s not good enough to advise people simply ‘not to travel’.— Dr Rosena Allin-Khan (@DrRosena) November 19, 2018
Meanwhile, gates are shut and queues are forming outside Earlsfield Station. @SW_Help @networkrail - go there and advise them! pic.twitter.com/2asSGkvE0e
Anthony Smith, chief executive of the independent watchdog Transport Focus, said: "Passengers rely on the railway - this morning tens of thousands of passengers coming into Waterloo could not.
"While engineering and improvement works need to be done, such late notice of the fundamental problems on the approaches to Waterloo this morning is unacceptable."
Passengers are entitled to "delay repay" compensation if cancellations cause delays to their journey of 15 minutes or more.
The amount varies depending on the length of the delay and whether someone is using a single, return or season ticket.
An annual season ticket between Surbiton and London Waterloo, the route that was closed, costs £1,912.