The youngsters drew the 7,000 yard train using 10,000 boxes of chalk in Cluj, Transylvania, Romania.
The world record, which they set last year, has been confirmed by the World Records Academy.
The drawing started as a school game but gradually grew as teachers and other pupils started to join in.
“We didn’t mean to break a record. We just kept going until we ran out of pavement. Thank goodness the rain kept off," said one organiser. (roundup)