A self-drive wine tour on Korčula is realistic, but Croatia's strict drink-driving law makes one decision unavoidable: who stays sober. The legal limit is 0.5 g/L for ordinary drivers and 0.0 g/L for novice drivers under 24, professionals and over-3.5 t vehicles, under Article 199 of the Road Traffic Safety Act (consolidated text NN 145/2024). Fines run €390–660 at 0.5–1.0 g/L, €660–1,990 at 1.0–1.5 g/L, and €1,320–2,650 or up to 60 days in jail above 1.5 g/L. On a Widmark estimate, two 150 ml glasses of 13% Korčulan white put an average 80 kg man near 0.57 g/L — already over the limit. One glass adds roughly 0.28 g/L for an 80 kg man or 0.40 g/L for a 70 kg woman, and the body clears only about 0.15 g/L per hour, so a second tasting pour usually means waiting or finding another driver. Korčula's two indigenous grapes sit at opposite ends of the island. Grk grows almost only in Lumbarda, about 6 km east of Korčula Town on sandy soil; only around 15 hectares exist anywhere and it is essentially never exported. Pošip comes from the central villages of Čara and Smokvica, 24–27 km west along the D118, and was the first Croatian white wine to win protected-origin status in 1967. A Lumbarda-only Grk afternoon is about 12 km round-trip and 30 minutes of driving; a full Grk-and-Pošip loop is about 66 km and 90 minutes at the wheel. Most Lumbarda cellars such as Bire and Popić are cash-only, while Toreta and Black Island in Smokvica take cards. If nobody can abstain, a private wine-tour driver costs from about €70, while taxis and the Lumbarda bus cover shorter hops.