Access to Vṛndāvana is only possible with the grace of Śrī Rādhā, who is the represented form of unlimited divine bliss, as well as the grace of Her expansions the Gopīs.
"Vaidhī-Bhakti, isto é aprendizagem. Bhakti verdadeira, Parā-Bhakti, é Rāgānugā-Bhakti." (Śrīla Prabhupāda)