Delhi's Old Delhi packs the Red Fort, Jama Masjid, and Chandni Chowk's market alleys, with New Delhi's Lutyens-era Connaught Place and India Gate, and Agra's Taj Mahal three hours south by Yamuna Expressway.
Cool dry season with Taj Mahal at peak photographic conditions, Delhi air pollution heaviest in November, and Republic Day parade January 26 along Rajpath.
Hot dry season with Delhi hitting 40°C and Taj walking punishing by 10am, but Holi colour festival mid-March across the country brings the year's most joyful streets.
Monsoon brings afternoon storms and Delhi humidity, but Independence Day August 15 fills the Red Fort, and the Taj's gardens at peak greenery.
Diwali festival of lights in October-November turns Old Delhi into the country's most photogenic illumination, with markets full of sweets and oil-lamp light.