Celebrations also include mass ride in Hyde Park and women-only ride in Regent's Park...

Londoners and visitors to the city will be able to celebrate the fourth anniversary of the launch of the Barclays hire scheme by borrowing bikes for free the weekend after next, while the number hires last month is believed to have been the highest ever.

The scheme was launched on 30 July 2010, and on 16 and 17 August, people will be able to ride the bikes free for up to half an hour at a time without being charged the usual £2 daily fee non-members have to pay to access the scheme.

Mayor of London, Boris Johnson, said: "In my experience there is no greater way to enjoy London than on two wheels and to celebrate our fantastic cycle hire scheme's fourth birthday, we are offering everyone the chance to cycle around our beautiful city for free.

“Whether you are an avid enthusiast or a cycling novice, you'll be able to hop on a bike and take in some of our capital's most iconic sights."  .

Meanwhile, Transport for London says that the number of hires during July was set to break the record set during the 2012 Olympic Games, with more than 1.17 million hires during the month.

There was also a 30 per cent increase in the number of trips made between March and June, although there are suggestions that growth in the number of trips is due to the expansion of the scheme into South West London, as well as reflecting a dip in usage levels last year after the daily fee for hiring was doubled to £2.

Besides the free bike hire the weekend after next, there will also be a group ride in Hyde Park on Saturday 16 August and a women-only ride in Regent’s Park on Sunday 17 August. Both events are free to attend, with TfL providing bikes. Advance registration is needed for both via the Go Sky Ride website.

The organisation’s general manager for Barclays Cycle Hire, Nick Aldworth, said: "We've had a fantastic four years on Barclays Cycle Hire, with the distinctive bikes now firmly part of daily life in London. 

“We're set to break our previous record for the number of hires this month, with over 1,170,000 hires.  

"If you haven't tried the bikes before, you can give them a go for free during the weekend of Saturday 16 and Sunday 17 August.

“Riding with others can be fun so we've also teamed up with British Cycling to offer guided group rides in two lovely central London parks.   

"From Notting Hill to Canary Wharf and Camden to Clapham Junction, people are discovering how pleasant and handy it is to hop on our bikes to get around town. So come and celebrate this special anniversary with us, and get pedalling," he added.

Barclays' sponsorship of the scheme is due to end next year and currently TfL is running a tender process t select a replacement partner that will pay at least £7.5 million a year over the next five years to back it.

Born in Scotland, Simon moved to London aged seven and now lives in the Oxfordshire Cotswolds with his miniature schnauzer, Elodie. He fell in love with cycling one Saturday morning in 1994 while living in Italy when Milan-San Remo went past his front door. A daily cycle commuter in London back before riding to work started to boom, he's been news editor at road.cc since 2009. Handily for work, he speaks French and Italian. He doesn't get to ride his Colnago as often as he'd like, and freely admits he's much more adept at cooking than fettling with bikes.