SB 5.20.18
tatha ghrtodad bahih krauñcadvipo dvi-gunah sva-manena ksirodena parita upaklpto vrto yatha kusadvipo
ghrtodena yasmin krauñco nama parvata-rajo dvipa-nama-nirvartaka aste.
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Outside the ocean of clarified butter is another island, known as Krauñcadvipa, which has a width of 1,600,000 yojanas [12,800,000 miles], twice the width of the ocean of clarified butter. As Kusadvipa is surrounded by an ocean of clarified butter, Krauñcadvipa is surrounded by an ocean of milk as broad as the island itself. On Krauñcadvipa there is a great mountain known as Krauñca, from which the island takes its name.