Two weeks is the length at which Sri Lanka stops feeling like a checklist. This route covers the Cultural Triangle, the hill country and the south coast without a single day of more than four hours in the car.
We built it after too many clients came back saying the twelve day version had been half an hour too long in the car, three times over. Everything here is moveable. Swap Yala for Wilpattu, add three nights on the east coast, or take the whole thing slower still.