CC Madhya 18.12

śrī-rādheva hares tadīya-sarasī preṣṭhādbhutaiḥ svair guṇair
yasyāṁ śrī-yuta-mādhavendur aniśaṁ prītyā tayā krīḍati
premāsmin bata rādhikeva labhate yasyāṁ sakṛt snāna-kṛt
tasyā vai mahimā tathā madhurimā kenāstu varṇyaḥ kṣitau
Synonyms: 
śrī-rādhā — Śrīmatī Rādhārāṇī; iva — like; hareḥ — of Kṛṣṇa; tadīya — Her; sarasī — lake; preṣṭhā — very dear; adbhutaiḥ — by wonderful; svaiḥ — own; guṇaiḥ — transcendental qualities; yasyām — in which; śrī-yuta — all-opulent; mādhava — Śrī Kṛṣṇa; induḥ — like the moon; aniśam — incessantly; prītyā — with great affection; tayā — in association with Śrīmatī Rādhārāṇī; krīḍati — performs pastimes; premā — love; asmin — for Lord Kṛṣṇa; bata — certainly; rādhikā iva — exactly like Śrīmatī Rādhārāṇī; labhate — obtains; yasyām — in which; sakṛt — once; snāna-kṛt — one who takes a bath; tasyāḥ — of the lake; vai — certainly; mahimā — glories; tathā — as well as; madhurimā — sweetness; kena — by whom; astu — can be; varṇyaḥ — described; kṣitau — on this earth.
Translation: 
“ ‘Because of its wonderful transcendental qualities, Rādhā-kuṇḍa is as dear to Kṛṣṇa as Śrīmatī Rādhārāṇī. It was in that lake that the all-opulent Lord Śrī Kṛṣṇa performed His pastimes with Śrīmatī Rādhārāṇī with great pleasure and transcendental bliss. Whoever bathes just once in Rādhā-kuṇḍa attains Śrīmatī Rādhārāṇī’s loving attraction for Śrī Kṛṣṇa. Who within this world can describe the glories and sweetness of Śrī Rādhā-kuṇḍa?’ ”
Purport: 

This verse is found in the Govinda-līlāmṛta (7.102).