Extra transport services have been laid on in London as the 48-hour Tube strike takes place.
There will be 100 extra buses, extra river services, escorted cycle rides into central London and extra bike parking, Transport for London said.
Rail, Maritime and Transport Union (RMT) members began their 48-hour strike at 1859 GMT in a dispute over pay and proposed job cuts.
Normal Tube services are not expected to resume until Friday morning.
The strike, expected to affect all lines, was triggered following an RMT ballot last month that saw 2,810 members voting for the walk-out while 488 voted against it.
Docklands Light Railway and London overground services will operate as normal.
National rail operators will accept Oyster cards on rail routes "that mirror Tube journeys" in Greater London on Wednesday and Thursday, a TfL spokesman said.
"This will help alleviate some of the congestion, while ensuring people don't take advantage of the strike by using their Oyster cards on unrelated journeys," he added.
On Wednesday TfL volunteers will escort cyclists into central London from locations in Finsbury Park, Mile End, Ravenscourt Park, Brixton Road and Swiss Cottage at 0745 BST.
The volunteers leading this guided cycle route, named "BikeTube", will also provide maps and refreshments.
On Wednesday and Thursday, Transport for London (TfL) staff will be on hand across the bus network and at Tube stations to offer travel advice and will be distributing walking maps in central London.
'Very fair deal'
On Friday, London Underground offered staff a four-year deal of 1.5% this year and then the inflation rate plus 0.5%; or a two-year deal of 1% now and inflation plus 0.5% in year two.
But the RMT wants a 5% pay rise and a promise of no compulsory redundancies.
The RMT is also planning to strike over TfL's planned £2.4bn efficiency savings package across the whole network - buses, trams and Docklands Light Railways as well as the Tube.
The union has warned the savings plan could lead to compulsory redundancies.