When the Provincials get word that the British plan to occupy the no man's land at Bunker Hill and Dorchester Heights, they send Massachusetts and Connecticut militia to build defenses on Bunker Hill. The soldiers instead build the defenses on Breed's Hill, a smaller hill just next to Bunker Hill.
The British take most of the following day moving regulars across Boston Harbor to attack the defenses with overwhelming force. The provincials use the extra time to reinforce and extend their defenses, but get no significant reinforcements all day.
A cannon duel over the day accomplishes little except to show how amateurish and incompetent the provincial artillery really is. By late afternoon, British General William Howe is prepared to take the hill with overwhelming force.
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