Shinjuku is the city at full volume, and the trick is to take it in the right order: the towers first, then the lanes, then the garden that switches the sound off.
Start out of the west exit and walk to the Tokyo Metropolitan Government Building, where the observation deck is free and, on a clear evening, Fuji sits black against the sunset. Come down and cross east into Omoide Yokocho — Memory Lane, a smoky run of grilled-skewer stalls by the tracks where you eat standing and don't linger over the menu. Then the edge of Kabukicho, which you can take or leave; I'd take the neon and leave the rest. Golden Gai is the reason you came at this hour — six alleys of bars built for six drinkers each, best before they fill. Slip into Hanazono-jinja for a minute of vermilion quiet, proof the old city is still threaded through the new.
End south at Shinjuku Gyoen, the great garden, and let the towers fall away behind the wall. The Marunouchi line from Shinjuku-gyoemmae takes you out.
