When a man covering his face with a hat and a scarf walked out of the Carlton Hotel in Cannes in July with an estimated $136 million in diamonds and jewels, many assumed it was the largest theft in history. But there have been even bigger ones. Most have one thing in common: Whether or not the perpetrators are tracked down, the loot seldom is. Here are the biggest in the half-century since 1963, the year of the $49 million Great Train Robbery, all inflation-adjusted.City Bonds London, 1990
$933 MILLION A messenger was robbed at knifepoint while carrying T-bills and certificates of deposit. Later a fence was caught in an attempted sale to undercover agents, and most of the money was recovered.Isabella Stewart Gardner Museum
Boston, 1990 $536 MILLION Two men dressed as cops tied up guards and made off with 13 masterpieces. The FBI now says it may have identified the thieves but doesn’t know where the art is.Dar Es Salaam Bank Baghdad, 2007
$318 MILLION Security guards took cash from a private bank in the middle of the night. They were thought to have avoided detection with the help of local militant groups and were never caught.British Bank of the Middle East Beirut, 1976
$144 MILLION Armed thugs stormed the bank and took cash, gold and jewels. The robbery has never been solved, and the PLO, Phalangists and British special forces have all been rumoured to have been involved.Knightsbridge Safe Deposit London, 1987
MILLION Valerio Viccei, an Italian gangster, got past the staff and raided the vault. He was caught when he went to collect his Ferrari, served time and later died in Italy in a gunfight with police.
Image:Top: Alexander Klein / AFP / Getty Images; Museum: Paul Marotta / Getty Images; Gold: Paul Katz / Getty Images
(This story appears in the 20 September, 2013 issue of Forbes India. To visit our Archives, click here.)