One verse

Srimad Bhagavatam 5.20.2

5.20.2

जम्बूद्वीपोऽयं यावत्प्रमाणविस्तारस्तावता क्षारोदधिना परिवेष्टितो यथा मेरुर्जम्ब्वाख्येन लवणोदधिरपि ततो द्विगुणविशालेन प्लक्षाख्येन परिक्षिप्तो यथा परिखा बाह्योपवनेन । प्लक्षो जम्बूप्रमाणो द्वीपाख्याकरो हिरण्मय उत्थितो यत्राग्निरुपास्ते सप्तजिह्वस्तस्याधिपति: प्रियव्रतात्मज इध्मजिह्व: स्वं द्वीपं सप्तवर्षाणि विभज्य सप्तवर्षनामभ्य आत्मजेभ्य आकलय्य स्वयमात्मयोगेनोपरराम ॥ २ ॥

jambudvipo ’yam yavat-pramana-vistaras tavata ksarodadhina parivestito yatha merur jambv-akhyena lavanodadhir api tato dvi-guna-visalena plaksakhyena pariksipto yatha parikha bahyopavanena; plakso jambu-pramano dvipakhyakaro hiranmaya utthito yatragnir upaste sapta-jihvas tasyadhipatih priyavratatmaja idhmajihvah svam dvipam sapta-varsani vibhajya sapta-varsa-namabhya atmajebhya akalayya svayam atma-yogenopararama.

jambu-dvipah
Jambudvipa, the island named Jambu
ayam
this
yavat-pramana-vistarah
as much as the measure of its width, namely 100,000 yojanas (one yojana equals eight miles)
tavata
so much
ksara-udadhina
by the ocean of salt water
parivestitah
surrounded
yatha
just as
meruh
Sumeru Mountain
jambu-akhyena
by the island named Jambu
lavana-udadhih
the ocean of salt water
api
certainly
tatah
thereafter
dvi-guna-visalena
which is twice as wide
plaksa-akhyena
by the island named Plaksa
pariksiptah
surrounded
yatha
like
parikha
a moat
bahya
external
upavanena
by a gardenlike forest
plaksah
a plaksa tree
jambu-pramanah
having the height of the jambu tree
dvipa-akhya-karah
causing the name of the island
hiranmayah
magnificently splendorous
utthitah
rising
yatra
where
agnih
a fire
upaste
is situated
sapta-jihvah
having seven flames
tasya
of that island
adhipatih
the king or master
priyavrata-atmajah
the son of King Priyavrata
idhma-jihvah
named Idhmajihva
svam
own
dvipam
island
sapta
seven
varsani
tracts of land
vibhajya
dividing into
sapta-varsa-namabhyah
for whom the seven tracts of land were named
atmajebhyah
to his own sons
akalayya
offering
svayam
personally
atma-yogena
by the devotional service of the Lord
upararama
he retired from all material activities

As Sumeru Mountain is surrounded by Jambudvipa, Jambudvipa is also surrounded by an ocean of salt water. The breadth of Jambudvipa is 100,000 yojanas (800,000 miles), and the breadth of the saltwater ocean is the same. As a moat around a fort is sometimes surrounded by gardenlike forest, the saltwater ocean surrounding Jambudvipa is itself surrounded by Plaksadvipa. The breadth of Plaksadvipa is twice that of the saltwater ocean—in other words 260,000 yojanas (1,600,000 miles). On Plaksadvipa there is a tree shining like gold and as tall as the jambu tree on Jambudvipa. At its root is a fire with seven flames. It is because this tree is a plaksa tree that the island is called Plaksadvipa. Plaksadvipa was governed by Idhmajihva, one of the sons of Maharaja Priyavrata. He endowed the seven islands with the names of his seven sons, divided the islands among the sons, and then retired from active life to engage in the devotional service of the Lord.