Valmiki Ramayana Ayodhya Kanda Sarga 46 Shloka 14

तमसातीरे on the bank of Tamasa, वृक्षदलैः with leaves of trees, कृताम् made, तां शय्याम् that bed, वीक्ष्य having seen, रामः Rama, सभार्यः along with his wife, सौमित्रिणा सार्धम along with Lakshmana, संविवेश ह lay down.

Having seen the bed of leaves made ready on the bank of Tamasa, Rama lay down there along with Sita and Lakshmana.