Jungle warfare, throughout human history of warfare, is undoubtedly the most headache-inducing type of combat.
Everyone knows urban combat incurs heavy casualties, but the casualties in jungle warfare are not any less significant. Large-scale jungle wars in human history are much less frequent than urban warfare, but each jungle war is accompanied by an extremely high casualty rate.
In military terms, jungle warfare usually refers to battles that occur in tropical forests, and the greatest trouble with jungle warfare lies in the fact that forests provide unparalleled concealment for both parties involved.