Srimad-Bhagavatam: Canto 5 - Chapter 1 - Verse 11
Sanskrit:
मन्दरो मेरुमन्दर: सुपार्श्व: कुमुद इत्ययुतयोजनविस्तारोन्नाहा मेरोश्चतुर्दिशमवष्टम्भगिरय उपक्लृप्ता: ॥ ११ ॥
ITRANS:
mandaro merumandaraḥ supārśvaḥ kumuda ity ayuta-yojana-vistāronnāhā meroś catur-diśam avaṣṭambha-giraya upakḷptāḥ.
Translation:
On the four sides of the great mountain known as Sumeru are four mountains — Mandara, Merumandara, Supārśva and Kumuda — which are like its belts. The length and height of these mountains are calculated to be 10,000 yojanas [80,000 miles].