Two Polish tourists were plucked to safety by an RNLI London lifeboat crew after they were cut off by the rising tide at Butler's Wharf near Tower Bridge.
The tourists, a man and a woman in their twenties, were walking along the beach at Butler's Wharf when the fast-rising tide cut off their only route back to the riverside path above.
The Royal National Lifeboat Institution's (RNLI) Tower lifeboat crew launched into action at around 3pm on Saturday 23 May following a 999 call for help to the Coastguard.
Stan Todd, RNLI lifeboat helmsman, said: "When we arrived we could see the two standing on the 3ft of shore that was left exposed.
"It would not have been long before the area they were standing on was completely covered by water.
"I think they were shocked at how fast the tide had risen and cut off their way back up to the Thames Path above.
"We got them on board the lifeboat, gave them lifejackets and dropped them off at Tower Pier.'
Steve King, who is also an RNLI helmsman at Tower lifeboat station, said: "From time to time we do get called out to people cut off by the tide along the River Thames in London, particularly in the nice weather when people walk along the foreshore.
"The problem is they don't realise how fast the water rises and it's all too easy to get caught out.
"We would urge everyone to take extra care when spending time by the river, check tide times and always be aware of what the tide is doing around you.
"If you do find yourself in danger or see someone else in need of rescue, call 999 and ask for the Coastguard who will request the launch of an RNLI lifeboat."