On Saturday 23rd of June 1894, when just before four o'clock in the morning, a massive explosion ripped through the underground workings killing 290 men and boys, the worst mining disaster in South Wales to that date and only to be surpassed by the explosion at the Universal Colliery Senghenydd in 1913. Many of the bodies brought to the surface were so badly mutilated that identification was virtually impossible and there was several instances of corpses being carried to the wrong houses. Almost everyone in the community lost someone in the disaster; one particular family in Howell Street lost eleven members of the household. The father, four sons and six lodgers were all killed.
There were 125 horses employed underground at the time of the explosion, all but two were killed.