Once upon a time, the cowherd men of Vṛndāvana, headed by Nanda Mahārāja, desired to go to Ambikāvana to perform the Śivarātri performance. The rāsa-līlā was performed during the autumn, and after that the next big ceremony is Holi or the Dolayātrā ceremony. Between the Dolayātrā ceremony and the rāsa-līlā ceremony there is one important ceremony which is called Śivarātri, which is especially observed by the Śaivites, or devotees of Lord Śiva. But sometimes the Vaiṣṇavas also observe this ceremony because they accept Lord Śiva as the foremost Vaiṣṇava. But the function of Śivarātri is not observed very regularly by the bhaktas, or devotees of Kṛṣṇa. Under the circumstances, it is stated in Śrīmad-Bhāgavatam that the cowherd men headed by Nanda Mahārāja "once upon a time desired." That means that they were not regularly observing the Śivarātri function but that once upon a time they wanted to go to Ambikāvana out of curiosity. Ambikāvana is situated somewhere in the Gujarat province. Ambikāvana is said to be situated on the river Sarasvatī, yet we do not find any Sarasvatī River in the Gujarat province; the only river there is Savarmati. In India, all the big places of pilgrimage are situated on nice rivers like the Ganges, Yamunā, Sarasvatī, Narmadā, Godāvarī, Kāverī, etc. Ambikāvana was situated on the bank of Sarasvatī, and all the cowherd men and Nanda Mahārāja went there.