Check in around Connaught Place or Karol Bagh for central access. Use the metro from the airport to your hotel to avoid traffic and understand the city's transit layout from day one. New Delhi Railway Station and Hazrat Nizamuddin are the two major rail hubs; confirm which one your Agra departure uses tonight and note the pre-booking requirement for Gatimaan Express.

Begin Old Delhi with Jama Masjid, India's largest mosque, built in 1656 by Mughal Emperor Shah Jahan. Climb the south minaret for a panoramic view over the old city's rooftop landscape for a fee. The mosque courtyard can accommodate 25,000 worshippers and the architecture sets the tone for the Mughal scale you will see throughout this circuit.

Walk down the lane into Chandni Chowk, one of Asia's oldest markets. The Paranthe Wali Gali (Street of Parathas) is a compact lane of shops that have been frying stuffed flatbreads in the same ghee-deep pans since the 1870s. Try radish, paneer, or mixed stuffed paratha with accompanying pickles and yogurt. Do not rush this experience.

For the Chandni Chowk food trail, the sequence works best as: kachori at a street stall, jalebi from Haldiram area vendors, then a sit-down paratha. Keep the volumes moderate since Delhi's afternoon heat and continued walking can make an over-full stomach uncomfortable.

Use the metro to reach India Gate in the late afternoon for a wide open-space contrast to the dense lanes of Old Delhi. The Rajpath boulevard (now Kartavya Path) area is cleaned up and walkable, and the war memorial adds historical weight to an otherwise recreational space.

Evening plan: India Gate drive by auto or walk, then an early dinner before rest. Tomorrow is a monument-heavy day requiring a 6:30 AM start for Qutub Minar and Humayun's Tomb in the right light.