The Long Āgama Sūtra 2.36

2.36

爾時，世尊於羅閱祇隨宜住已，告阿難言：「汝等皆嚴，吾欲詣竹園。」

After staying in Rājagṛha for as long as was fitting, the Bhagavān told Ānanda, “All of you, get ready. I’m going to visit the Bamboo Park.”