THE LONGEST BLACKOUT
THE LONGEST LIST OF THE LONGEST STUFF AT THE LONGEST DOMAIN NAME AT LONG LAST

So what exactly was the longest blackout in the world?

Date:                    February 19 1998
Location:            Auckland, New Zealand
Length:               66 days
Cause:                4 power cables broke down
 

Notes: 7500 businesses and residents were affected. Estimated loss due to the power failure was $156 million USD.