Boukephala (Ancient Greek: Βουκεφάλα) and Nikaia (Νίκαια) were two cities founded by Alexander the Great on either side of the Hydaspes (modern-day Jhelum River, Pakistan) during his invasion of the Indian subcontinent.

Boukephala seems to have had a more distinguished legacy than Nikaia: mentioned by Pliny the Elder and Ptolemy, it appears in the 1st-century AD Periplus Maris Erythraei manuscript and on the later Tabula Peutingeriana map.

[3] Before moving onwards to continue his Indian campaign, Alexander celebrated his victory and foundations with what Arrian terms "a gymnastic and horse contest" near the western city.

The troops were ordered to help repair damage caused by the monsoon, a phenomenon previously unknown to the Macedonians, whose buildings were not designed to withstand heavy rains.

[5] There is some dispute as to whether Alexander intended his foundations to be rapidly developing cities or military garrisons which would control the conquered territory; the historian N. G. L. Hammond theorised that Boukephala and Nikaia, founded on the banks of a major river, must have been established with trade routes in mind.

[6] According to Arrian, Alexander may have established dockyards at Boukephala, although Curtius Rufus states that these were located on the Acesines (modern-day Chenab River).

[14] Meanwhile, the Indian historian A. K. Narain questioned whether Boukephala still existed by the time of Menander I (c.150 BC), but this uncertainty is dispelled by the city's presence in the 1st-century AD Periplus of the Erythraean Sea, a guide for Roman merchant sailors.

[15] Boukephala appears in many other Greco-Roman texts, including various recensions of the Alexander Romance and the writings of Ptolemy, and Pliny the Elder, who names the city as the chief of three controlled by the Asini tribe.

[21] A monument to the life of Alexander was thus built between 1998 and 2011 near the town; funded by the Government of Pakistan, the Greek embassy in Islamabad, and by private donations, it had become dilapidated by 2023.

[24] A reference to the two cities may appear in the Mulasarvastivada Vinaya, a tripitaka text of an early Buddhist school which likely dates from the time of the Kushan emperor Kanishka (r. c. 127 – 150 AD).

[7] Similarly, an old Hindu tradition at a shrine to Mangla Devi at the site of Garjak above Jalalpur includes the story of the death of a magical horse.