Matsya Purana 188.73

188.73

evaṃ tu tripuraṃ dagdhaṃ śaṅkareṇa mahātmanā.
jvālamālāpradīptaṃ tatpatitaṃ dharaṇītale .. 188.73 ..

"For this reason the Lord did not consume his third Pura, which is sailing about the sky by the power of Śiva The other two Puras fell down to the ground after being reduced to the ashes Śrīśaila mount was formed on the spot where the first city fell and similarly Amarakaṇṭaka sprang up on the spot where the second Pura fell down"—72 74