The first four characters (BARB) represents that it belongs to Bank of Baroda. The fifth character (0) is reserved for future use. The last 6 characters (PATNAB) represents that it belongs to Patna Main Patna branch in district Patna of Bihar.
IFSC code (BARB0PATNAB) can be found on the front page of the account holder's passbook or in cheque leaf. You can also verify the same by contacting bank authority of Bank of Baroda since data here could be outdated.
Patna Main Patna branch of Bank of Baroda is in Bihar state of India.
Fraser road, Patna-800001