Repairing damage caused by a blaze the size of the Great Fire of London in 1666 would cost insurers at least £37 billion ($65.3 billion) today, the Association of British Insurers (ABI) estimates.

“The Great Fire of London led to the modern insurance industry we know today,” ABI Director of General Insurance Policy James Dalton says.

“The damage of the fire was on an unprecedented scale and it is difficult to imagine now that no insurance policies were in place for any of the damage caused.”

The ABI has released the damage calculation and a timeline for the fire before the disaster’s 350th anniversary on September 2.

The fire started in a bakery on Pudding Lane and destroyed more than 13,500 homes and 87 churches, including St Paul’s Cathedral.

Homeowners had no guarantee they could rebuild their properties or replace belongings, because property insurance did not exist, the ABI says.

“This led to many people, including the famous Samuel Pepys, running to their gardens to bury valuables such as cheese and wine.”

The ABI says estimated costs were £10 million ($17.6 million) in the 17th century.

Ecclesiastical Insurance says the cost of rebuilding St Paul’s was £700,000. The rebuild would cost about £600 million ($1.06 billion) today.