" 'Just as Srimati Radharani is most dear to SriKrsna, Her bathing place known as Radha-kunda is also dear to Him. Among all the gopis, Srimati Radharani is supermost and very dear to Lord Krsna.'
This verse is from the PadmaPurana and is included in the Laghu-bhagavatamrta (2.45), by SrilaRupa Gosvami. It also appears in Adi-lila, Chapter Four, verse 215, and again in Madhya-lila, Chapter Eighteen, verse 8.