The long run, not the easy one — 24–26km of Grade III–IV water through rapids like Three Blind Mice, Cross Fire, Black Money and Roller Coaster, and a half day gone once you count the upstream drive and the briefing. Most operators set a minimum age of 18 on this stretch against 8–14 on the shorter ones, and it is longer and more demanding than Shivpuri, not gentler. Anything selling Marine Drive as a beginner float has the river backwards — the short beginner run is Brahmpuri. UTDB-licensed operators only, with a rescue kayaker on the water and a real pre-trip briefing, and confirm the day's actual route when you book: names, distances, minimum ages and approved put-in points all change with water level and government instructions.
Marine Drive is not a village but a long, straight section of the Rishikesh-Badrinath highway that runs beside the Ganga roughly 25km upstream of Rishikesh, and it lends its name to the put-in point and the riverside camping stretch beneath it. It became a standard commercial put-in as operators and the state-run Garhwal Mandal Vikas Nigam expanded beyond the flagship Shivpuri run through the 1990s and 2000s, filling the gap between that 16km trip and the harder Kaudiyala route further upstream. Because every route on this stretch finishes at the same take-out beaches near Rishikesh, a Marine Drive raft passes through the whole of the Shivpuri and Brahmpuri sections on its way down, which is why its rapid list carries the better-known names from the shorter trips.