The name refers to the United Irishmen and their supporters who were killed or executed during the 1798 rebellion, many of whom were buried here in a mass grave. The term "croppies" was a colloquial label for the rebels, derived from the close-cropped hairstyle associated with radical republican sentiment in that period, a deliberate echo of revolutionary France. That such a significant site of mass burial sits quietly beside a busy riverside esplanade, largely unmarked in the everyday consciousness of the city, is itself a kind of historical curiosity.

The site occupies a rectangular plot within the Esplanade, measuring roughly 94 metres in length and 51 metres in width, according to De Courcy's 1996 survey of the area. The 1798 rebellion was a watershed moment in Irish history, a failed insurrection inspired by Enlightenment ideals and supported in part by French military intervention, which was crushed with considerable brutality by Crown forces. Those who died in Dublin, whether in combat, by summary execution, or in custody, were not afforded individual burial rites in many cases. Croppies Acre became one of the destinations for these remains, a utilitarian solution to the aftermath of violent suppression. The proximity to what was then the Royal Barracks, now Collins Barracks and home to a branch of the National Museum of Ireland, is historically apt; the military infrastructure of the period and the consequences of rebellion were, in this instance, literally neighbours.

The site is located along the Liffey quays on the north side of the city, in the stretch between the barracks and the river. Visitors approaching from the city centre will find the Esplanade accessible on foot, running along Ellis Quay and Wolfe Tone Quay. There is no elaborate monument demanding attention, which means it is easy to pass through without registering what lies underfoot. The most useful orientation is simply to know the boundaries: that long, relatively narrow rectangle of ground south of the barracks walls. A visit to the nearby Collins Barracks museum can provide broader context for the military and political history of the period, making the two sites a natural pairing for anyone interested in late eighteenth-century Dublin.