Valmiki Ramayana Sundara Kanda Sarga 56 Shloka 32
Original Shlokaस च भूमिधरः श्रीमान्बलिना तेन पीडितः।।5.56.32।। सवृक्षशिखरोदग्रः प्रविवेश रसातलम्।
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बलिना by the powerful one, तेन by him, पीडितः crushed, सवृक्षशिखरोदग्रः along with its trees and standing tall peaks, श्रीमान् prosperous, सः भूमिधरश्च that mountain, रसातलम् underworld, प्रविवेश entered.
Crushed by the powerful Hanuman, that prosperous mountain with its trees standing and tall peaks sank into the underworld.