Renting a tuk-tuk and self driving the whole country for 3 weeks realistic

Completely realistic and increasingly popular. A few well-known nationwide tuk-tuk rental companies will hand you a fully prepped tuk with insurance, a phone holder, USB charger and 24/7 roadside support, plus they handle the AAC recognition permit conversion of your IDP. Costs for 2026: roughly 12 to 20 USD per day for a 3+ week rental, with no mileage cap on most plans. Speed is the killer detail: tuk-tuks top out at 40 to 50 km/h on a good road, so plan ~80 km per day, not 200. Worst stretches: the A2 south coast highway (heavy truck and bus traffic, drive only in daylight), the hill country switchbacks near Nuwara Eliya (steep, wet, slow), and central Colombo (avoid driving in unless you must). Best stretches for tuk-tuk: south coast back roads, the east coast, the cultural triangle. Never drive at night.