Valmiki Ramayana Kishkindha Kanda Sarga 37 Shloka 28
Original Shlokaतस्मिन्गिरिवरे रम्ये यज्ञो माहेश्वरः पुरा। सर्वदेवमनस्तोषो बभौ दिव्यो मनोहरः।।4.37.28।।
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रम्ये on the enchanting, तस्मिन् on that, गिरिवरे on the best of mountains, पुरा earlier, सर्वदेवमनस्तोषः made the minds of all deities happy, दिव्य: मनोहर: divine and wonderful, माहेश्वरः Lord Mahesvara, यज्ञः Yajna, बभौ was performed.
A divine, wonderful, delightful Yagna dedicated to Lord Siva used to be performed on the beautiful (Himalayan) mountain in the past so that the minds of all deities were satisfied.