Over a thousand swimming pools run by almost 300 local councils will offer free swimming from today, for children and the over 60s.

Four out of every five local councils in England have signed up to provide free swimming for over 60s, with more than 200 offering it too for young people. Twenty million people are eligible to swim for free, using pools in other areas if their own council is not participating in the scheme.

The £140 million Government initiative, announced last June, is a key part of the plans to ensure a long-term legacy from staging the Olympic and Paralympic Games in London.

It was launched today at the Eltham Centre in Greenwich, London, by Culture, Media and Sport Secretary Andy Burnham, Olympics Minister Tessa Jowell, new world 400m freestyle record holder Joanne Jackson, Paralympic gold medallist and new double world record holder Heather Frederiksen and Olympic swimmer and Strictly Come Dancing star Mark Foster.

Andy Burnham said:

'This is a landmark moment in our bid to build a healthier and more active nation. It is real evidence of our ambition to use the Olympic and Paralympic Games to lift sport in this country. It is also the day when London 2012 made a real difference on the ground, and to people up and down the country.

'We have worked with local councils of all political persuasions to seize the opportunity - and many of them are joining us in making a significant financial contribution to ensure its success.

'This scheme has caught the mood of the times. It will help young and old keep active and save cash. It is our hope that this is just the beginning and that in time free swimming becomes the norm.'

In total 288 councils across England (81 per cent of those eligible) will be offering free swimming from 1 April for the over-60s. And 207 local authorities (equivalent to 58 per cent) will also be providing it for children and young people aged 16 and under.

Until now only 10 councils offered any year-round free access.

Key details of the scheme:

* More than £31 million is going in the first year to local councils to help meet the cost of providing free access to pools during standard swimming sessions - and millions more will ensure a second year of free swimming in 2010/11;

* Councils that are providing free swimming for both age groups have already been allocated £10 million to improve their local facilities;

* A £50 million capital fund is being made available to councils to modernise existing facilities or help build new ones in 2009/10 and 2010/11. The first grants of £19.2 million are announced today for 54 projects - with the biggest awards of over £1 million going to improved or new facilities in the London boroughs of Southwark and Harrow, and Leicestershire, Calderdale, Nottingham and Waveney.

* A national network of swimming experts is being recruited to work with participating councils to promote interest in swimming and increase participation;

* One hundred thousand free swimming lessons are being offered to non-swimmers;

* Extra funding within the overall funding package is being promised to participating councils, including as a reward to those with the best record in developing the scheme and making an impact in their communities;

* Local councils will be eligible to seek London 2012's 'Inspire' mark, as recognition of the impact of their schemes in producing a lasting legacy from hosting the Olympic and Paralympic Games in 2012;

* The initiative is guaranteed to run for at least two years - the period covered by the Government's current spending review.

Communities and Local Government Secretary Hazel Blears said: 'I am delighted that nearly 300 councils have taken the plunge and dipped into the Government funding, and in some cases their own pool of resources, to offer free swimming to their local communities.

'Swimming is a great way for people of all ages to keep fit and healthy - so I would encourage all those 16 and under and over 60 who will now qualify to swim for free to dive in and make the most of this valuable opportunity. And I look forward to seeing more councils sign up to this exciting new scheme.'