Valmiki Ramayana Yuddha Kanda Sarga 69 Shloka 63

संयुगे in combat, तैः they, पर्वत mountains चिनैः broken, द्रुमैः trees, हतैः killed, कपिरक्षोभिः च Vanaras and Rakshasas, विकीर्णै covered, वसुधा earth, दुर्गमा difficult to tread, अभवत् seemed.

The battlefield, covered with broken trees and mountains, fallen vanaras and rakshasas, seemed difficult to tread on ground.