The Longest boxing match 110 Rounds
photo via Philippines Shocking History
On April 6,1893, fighters Andy Bowen and Jack Burke competed at the New York's Olympic Club in the hopes of taking home the winner take all purse prize of $2,500 to be given to the one who would fight to the finish.
Their fight ended after 110 rounds, running for 7 hours and 19 minutes with each round lasting 3 minutes each and with neither boxer pausing for a break. The two ended up splitting the Prize.