By air - The nearest airport is Jolly Grant Airport in Dehradun, roughly 20–45 km away (about 30–45 minutes by road) depending on which part of Rishikesh you're headed to. It has regular flights from Delhi.
By train - Rishikesh has its own small railway station, but most long-distance trains actually terminate at Haridwar Junction, about 20–25 km away — the better-connected major station for the region. From there it's a short taxi, shared auto, or bus ride.
By road - Rishikesh sits on NH 58, the main route toward Badrinath, and is well connected by bus and taxi to Dehradun, Haridwar, Delhi, and other Uttarakhand towns. Buses from Haridwar's railway-station bus stand run roughly every 10–15 minutes.