The annual Navratri Brahmotsavam celebrations 2017 in Tirumala Tirupati Balaji temple will begin on September 23, 2017 and end on October 1, 2017. During the nine-days of the Brahmotsavams, Sri Venkateswara will be taken in procession around the temple in different Vahanas (special decorated Vehicles based on Vishnu legends). There will be special Unjal Seva during the period.
September 23, 2017 – Dwarjarahanam (Morning) Pedda Sesha Vahanam (Evening)
September 24, 2017– Chinna Sesha Vahanam (Morning) Hamsa Vahanam (Evening)
September 25, 2017 – Simha Vahanam (Morning) Muthyapu Pandiri Vahanam (Evening)
September 26, 2017– Kalpa Vruksha Vahanam (Morning) Sarva Bhoopala Vahanam (Evening)
September 27, 2017 – Mohini Avatharam (Morning) Garuda Vahanam (Evening)
September 28, 2017 – Hanumantha Vahanam and Swarna Ratham (Morning) Gaja Vahanam (Evening)
September 29, 2017 – Surya Prabha Vahanam (Morning) Chandra Prabha Vahanam (Evening)
September 30, 2017– Rathostavam (Morning) Aswa Vahanam (Evening)
October 1, 2017 – Chakra Snanam (Morning) Dwaja Avarohanam (Evening)
More information about various Vahanas during Navratri Brahmotsavam can be found in this earlier article.