The Patriots' Day bombing occurred in 2013. The central subject of the query, "Patriots Day bombing," functions as a compound noun identifying a specific event. The interrogative seeks to identify the "year," which is also a noun, associated with this event.
The attack took place on Monday, April 15, 2013. Two homemade pressure-cooker bombs detonated near the finish line of the annual Boston Marathon, an event held on Patriots' Day, a civic holiday in Massachusetts. The date and location are key factual nouns that define the historical context of the event.
While described using the term "Patriots Day bombing," the event is most widely and officially known as the Boston Marathon bombing. This proper noun has become the standard reference for the 2013 terrorist attack in Boston.
