An education at the UK's leading universities is being denied to state-school pupils from vast swathes of the country, according to a report released today.
A study by the Sutton Trust on the university chances of pupils from individual schools has revealed a number of higher education "black spots" in England, where just a fraction of state-school students go on to study at the best universities.
It is the first time the figures detailing the higher education destinations of pupils from individual school sixth-forms and colleges have been published. They highlight the stark disparity between the chances of pupils living in the South East and the rest of the country, particularly the North West.
Students from areas such as Rochdale and Knowsley are 10 times less likely to attend one of the top 30 most selective universities than students from Hammersmith and Fulham, and 50 times less likely to study at Oxford or Cambridge.
Over the three-year period examined in the report, 2007 to 2009, not a single student from Knowsley went on to study at Oxford or Cambridge. In Rochdale, just one of a potential 2,000 candidates over the three years went on to Oxbridge.
The report also states that just 12 local authorities send more than one in every 50 pupils to Oxbridge. Apart from Trafford in Greater Manchester, all of them are in the South.
But among the most startling figures in the report was the finding that four independent schools and one college - namely Westminster, Eton, St Paul's, St Paul's Girls' School, and Hills Road Sixth Form College - secured more Oxbridge places than 2,000 schools combined.
According to the study, these five institutions sent 946 students to either Oxford or Cambridge, as opposed to 927 from 2,000 schools or colleges.
Furthermore, the top 100 schools in the country - 87 independents and 13 grammars - accounted for more than a tenth of places at the most selective universities, even though they represented just 3 per cent of all the sixth-forms and sixth-form colleges in the country.
The figures echo education secretary Michael Gove's often repeated line that more students from one cohort at Eton secure more places at Oxbridge than all of the students on free school meals put together.
But Lee Elliot Major, director of research and policy at the Sutton Trust, said this statistic went further, revealing that Oxbridge is "out of bounds" for vast swathes of the country's students.
"Areas such as Reading are selective, so it may not come as much of a surprise it does well when it comes to its pupils going to the best universities," Dr Elliot Major said.
"But most people would think there are some people in their local area who may have gone to Oxford or Cambridge. To have none in an entire area is surprising."
And he added: "We know inequalities emerge early on in life, but what you want to see is less stark inequalities than is currently the case. The report shows there are real higher education black spots in the country."
Frank Gill, principal at Knowsley Sixth Form College, said the distance from home of universities like Oxford or Cambridge was a factor for many of his students, but added that feelings towards institutions of this type ran deeper.
"There is a reverse prejudice, if you like, when it comes to these universities, despite the good work our teachers do and the work of programmes such as Aimhigher," Mr Gill said.
"There will always be an inherent belief among families that these places are alien to them. I am sure that is a factor."
When looking at schools where students received similar results, independent schools in particular far outshone their comprehensive rivals.
Nearly nine in 10 students from the 30 independent schools with the highest progression to higher education were accepted at the best universities, whereas fewer than six in 10 made the same transition from comprehensives, despite achieving similar grades.
John Bangs, senior research fellow at Cambridge University, said it came down to social capital.
"It seems to me that the interview panels, particularly when we talk about Oxford and Cambridge, value the same capital that comes from independent schools and grammar schools (rather) than from comprehensives, such as in the books you read or whether you play rugby or cricket," he said.
Both Oxford and Cambridge pointed to results as the main contributing factor to students winning places, citing the quality of the exams students sit as particularly important, rather than the quantity.
Geoff Parks, director of admissions at Cambridge University, said many of the top schools select their pupils with an eye on the fact that they may be potential Oxbridge applicants.
"At these schools students are encouraged to aim high and are given proper advice as to which are the best subjects to take," Dr Parks said.
"In these schools the high-ability students are not held back. They are placed in sets or streams where the top set can go on and a strive for A grades.
"Without these situations it is likely students would be held back, unless the teachers are willing to go the extra mile and stay behind."
He added that since the introduction of tuition fees, students, particularly in the North, have tended to go to universities closer to home.
Oxford pointed to the uneven distribution of achievement across the school system. According to the university, its average applicant gains more than five A* grades at GCSE, and the average accepted student performs even better.
An Oxford University spokesperson said: "As a university trying to reach out to younger students, you could visit the top eight schools based on GCSE attainment and find 850 people with five A* grades or better.
"But you would have to visit the bottom 1,900 schools, with more than a quarter of a million students in total, to get the same number.
"That's why Oxford spends millions on outreach, running over 1,500 events a year and reaching 78 per cent of all schools with post-16 provision.
"Our priority is to ensure that, in schools where top attainment is rare, the one person who does achieve top grades is not disadvantaged by their relative isolation."