LONDON — Millions of commuters cycled, trudged, and waited in long bus lines Monday as a strike by London Underground station staff shut down much of the city’s subway network.

Scores of Tube stations and many of the city’s subway lines were closed during the morning rush hour. Some Londoners took to bicycles, weaving through slow-moving traffic. ‘‘It is really scary out there; cyclists are taking huge chances,’’ doctor Simon Quantrill said. ‘‘The traffic is mad.’’

Huge lines for taxis formed at major railway stations. One, Clapham Junction, was evacuated because of severe overcrowding.

The 24-hour strike ended at 6 p.m. local time, but Transport for London said service wasn’t expected to get back to normal until Tuesday morning.

Transport unions are protesting job cuts and ticket-office closures. ‘‘This action has been forced on us by savage cuts to jobs that have reduced London Underground to an under-staffed death trap at a time of heightened security and safety alert,’’ said Mick Cash, of the Rail, Maritime and Transport Union.

While acknowledging some issues needed to be addressed, London Mayor Sadiq Khan described the strike as ‘‘completely unnecessary.’’

Associated Press