Ecocide, incorporating either wilful or large-scale destruction of the environment, is a well-recognised problem, although it has still to come under the jurisdiction of international law. As instances of ecocide increase in both war and peacetime, the integrity of protected and conserved areas is increasingly compromised. Here, we highlight two forms of ecocide, namely broad-sense or large-scale environmental damage and narrow-sense or large-scale damage
with intent. Then we examine notable cases of both broad and narrow-sense ecocide affecting national parks. In the Supplementary Online Material, we review the historical and contemporary definitions of ecocide. There are now
significant efforts to establish effective legal frameworks aimed at criminalising ecocide, but these are advancing only slowly, and the threats to protected and conserved areas remain.