A contract dating back to AD 62 setting out an agreement to bring “twenty loads of provisions” from Verulamium to London has been revealed in an archaeological dig at a building site.

Excavations for Bloomberg’s new European headquarters in the capital have resulted in the finding of 405 Roman waxed writing tablets.

As previously only 19 legible tablets were known from London, the collection’s unearthing has been hailed as Britain’s largest, earliest and most significant collection of Roman waxed writing tablets.

In a statement, the Museum of London Archaeology (MOLA) said the tablets “provide an incredibly rare and personal insight into the first decades of Roman rule” as they showed the names, events, workings and organisation of the new city.

The tablet relating to St Albans harks back to its predecessor, Verulamium, which in its heyday was the third largest city of Roman Britain – our local museum in St Michael’s is named after it and stands on the site of that town.

With 87 of the writing tablets now deciphered by experts in cursive Latin, MOLA said that the one referring to the contract in AD 62 was organised a year after the Boudiccan Revolt against the Romans – when Londinium and Verulamium were burned and destroyed.

MOLA said it “reveals precious details of the rapid recovery of Roman London”.

However, the author of the 14cm-wide, eight centimetre high tablet made a mistake when writing about the impending delivery, writing ‘Lond’, meaning that they started to write Londinio instead of Verulamio, realised their mistake and deleted it. This deletion, says MOLA, which would have amounted only to smoothing out the wax, left no mark on the wood.

Roman barrels were also found during the dig – these were recycled to make writing tablets.

Made of wood, recesses in the rectangular tablets were originally filled with blackened beeswax, with text inscribed into the wax with styluses.