Spend three days in Varanasi: day one for arrival and the evening Ganga Aarti, day two for the sunrise boat ride, old city lanes and Kashi Vishwanath, and day three for Sarnath and a slow ghat afternoon. Base yourself near the ghats and keep October to March as the preferred season.
If you are asking what to do in Varanasi in 3 days, the short answer is a steady rhythm rather than a checklist....
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