CC Antya 2.16

āmbuyā-muluke haya nakula-brahmacārī
parama-vaiṣṇava teṅho baḍa adhikārī
Word for word: 
āmbuyā-muluke — in the province known as Āmbuyā; haya — there is; nakula-brahmacārī — a person known as Nakula Brahmacārī; parama-vaiṣṇava — a perfectly pure devotee; teṅho — he; baḍa adhikārī — very advanced in devotional service.
Translation: 
In Āmbuyā-muluka there was a person named Nakula Brahmacārī, who was a perfectly pure devotee, greatly advanced in devotional service.
Purport: 

Śrīla Bhaktivinoda Ṭhākura says that Āmbuyā-muluka is the present Ambikā, a city in the Burdwan district of West Bengal. Formerly, during the Muslim regime, it was known as Āmbuyā-muluka. In this city there is a neighborhood called Pyārīgañja, and that is where Nakula Brahmacārī used to live.