Poor public transport is contributing to the creation of underachieving schools across England, according to education analysts.
SchoolDash said badly connected areas, even ones without major deprivation, are more likely to have low-achieving secondary schools.
'Cut off' locations are also making it difficult to recruit staff – a key issue, according to consultant Anna Vignoles, a professor in education at Cambridge University, who highlighted the double impact on 'communities with low horizons'.
In a 'striking overlap', researchers found that, even in richer areas, poor transport seemed linked to lower school results.
As measures of distance the project used Department for Transport journey time statistics that show how long it takes by public transport to reach a major centre of employment.
The average travel time is 33 minutes, and the analysis shows how school results seem to worsen as journey times stretch beyond this, according to SchoolDash founder Timo Hannay.
Across secondary schools, 31% of those with fast public transport links are currently graded as outstanding by Ofsted. But, of the ones in places where travel times are slow, only 17% make it to the top rank.
While only 24% of schools overall are rated inadequate or requires improvement by Ofsted, of those in deprived areas that experience longer travel times, 66% of schools have received a low rating.
The same cold spots repeatedly recur in the findings - among them 'left behind' towns in the North West and North East, declining seaside towns in the South, and those along the Norfolk coast.
But other vulnerable areas include the edges of major cities, such as Manchester, Birmingham, Bristol and Newcastle, and pockets of Kent and the South West.
Mr Hannay was previously managing director of research software company Digital Science.