This paper compares two odes by Khāqāni Sharvani (12^th CE) in praise of two cities, namely one ode in Persian, in praise of Safāhān (an alternative form of the city name Isfahan) which begins as follows: Nakhat- i hawrā-st yā havā-yi Safāhān ‘is it the scent of the houri or the air of Isfahan?’, and the other in Arabic, in praise of Baghdad, which begins as follows: a-mašrab-u-l-Xiḍr-i māʾ-u Baġdāḏā ‘is Baghdad’s water the same Fountain of Youth achieved by al-Khadir?’ (the two odes are henceforth called Safāhāniyyah and Baġdādiyyah respectively). Due to the considerable resemblance between Safāhāniyyah and Baġdādiyyah in aspects such as the prosodic features, the content, the sequence of the themes, and even the puns and other literary techniques, both odes seem to be elaborately composed based on the same sketch, and therefore, I call Safāhāniyyah and Baġdādiyyah "two sister odes". Based on evidence from the odes, it is argued that Khāqāni composed Safāhāniyyah in 556 AH (i.e. almost one year after his two Hajj pilgrimages to Mecca, when he was younger than 35). 10-15 years later, he composed Baġdādiyyah based on the sketch of Safāhāniyyah, during the reign of the Abbasid caliph, al-Mustaḍīʾ bi-Amr Allāh (566-575 AH), before his third Hajj pilgrimage (571 AH) and likely, shortly before that pilgrimage journey. During the discussion, I emendate some of the couplets of Baġdādiyyah cited in the paper based on the early manuscripts of the Dīwān, since Khāqāni's Arabic verses have been recorded with numerous errors and corrupt readings in the modern editions. Furthermore, I introduce a manuscript of the Dīwān of Khāqāni, which, though relatively late, is a copy containing highly authentic and non-corrupt readings of the Arabic verses, and should be taken into consideration in a critical edition of the Diwān.