Aligarh is a city in western Uttar Pradesh, about 130 km southeast of Delhi and an easy side trip from Agra. It is best known as the home of Aligarh Muslim University, one of the most important educational institutions in South Asia, founded in 1875 by Sir Syed Ahmad Khan. The campus is worth visiting for its red-brick Indo-Saracenic buildings and the Jama Masjid at its centre.
Beyond the university, Aligarh is an industrial city known for its lock and hardware manufacturing — it produces the majority of locks made in India, and the Upper Kot Bazaar where the lock trade is centred is a genuinely interesting place to wander. The Aligarh Fort, partly used now as botanical gardens by the university, retains impressive ramparts and bastions. The city is not a major tourist destination, but travellers passing between Delhi and Agra may find it a worthwhile detour.