Millions of Londoners had a difficult journey to and from work on Wednesday as Underground workers began the first in a series of strikes.
The 48-hour walkout, to be followed by another next week, is in protest at ticket offices being closed and jobs lost in a modernisation drive.
Many tube stations have closed completely with reduced services running on some lines.
“It is a pain in the arse to be honest but it is fair enough,” said one commuter, Stefan Bornhoft. “They have to fight for their rights.”
But fellow London traveller Chris Nash opposes strike action: “Every company has to modernise,” he said.
“Every infrastructure in the world has to modernise. You can’t just stay stuck in time. If the ticket offices are moving through to automation, then you can’t just resist that and stop that from happening,” Nash added.
Some took to bicycles to get round the disruption on the world’s oldest metro system, dating from 1863.
Boat services on the River Thames have been running extra trips, with streets and buses jam-packed.
In parliament, British Prime Minister David Cameron said he “unreservedly” condemned the strike.