A cave on the side of Gijjhakūṭa, where the Buddha stayed. There he taught the Dīghanakha Sutta (Vedanāpariggaha Sutta) to Dīghanakha. Sāriputta was also present, and the sutta led to his attainment of Arahantship (M.i.497, 501; DhA.i.79; UdA.189).
A conversation which the Buddha had there with Sāriputta is recorded in the Saṃyuttanikāya (S.v.233 f). The Commentary says (SA.iii.197) that, in the time of Kassapa Buddha, this cave was found as a hollow in the ground when the earth was yet growing, during the interval between the two Buddhas. One day a boar dug up the soil in the neighbourhood of the ground which concealed the cave. The sky god sent rain which washed away the soil, and the cave was disclosed.
A forest dweller saw it and looked after it, thinking it to be the dwelling of holy men. He removed the earth round it, fenced it in, cleaned it out, and, making it as beautiful as a golden bowl, furnished it with couch and stool and presented it to the Buddha. The cave was deep and could only be reached by climbing.