The D.400 is Turkey's southern state road: 2,057 km (1,278 miles) from Datça, at the tip of the peninsula in the country's south-west corner, east along the whole Mediterranean coast and inland to the Iranian border at Esendere. Riders do not do all of it. The section worth planning a trip around is the western third — Datça to Alanya, about 626 km (389 miles) — where the road is cut into cliffs above the sea between Fethiye, Kaş and Antalya. That stretch is one of the best coastal roads in Europe or Asia, and it is a bad idea in August.
What the D.400 is
It is a Turkish state road rather than a scenic route with a name, which is part of its appeal — nobody built it for tourists. It starts at Datça, runs east through Marmaris at km 69 and Fethiye at km 195, hugs the Lycian coast through Kalkan, Kaş, Demre, Finike and Kemer, reaches Antalya at km 488, continues through Alanya at km 626 and Anamur at km 754, then Silifke, Mersin and Adana before turning inland through Gaziantep and Şanlıurfa. Between Nizip and Cizre it doubles as European route E90, and at the far end it links to Road 16 in Iran.
The character changes completely along its length. West of Antalya it is a two-lane mountain road on a cliff. East of Antalya through Alanya and Anamur it stays coastal but gets straighter and busier. Beyond Mersin and Adana it becomes a fast inland trunk road across the south-east, and that section is a different trip with different planning considerations. This guide covers the coast.
Route at a glance
| Road | D.400 state road, southern Türkiye |
| Full length | 2,057 km (1,278 miles), Datça to Esendere on the Iranian border |
| Coastal section | Datça to Alanya, about 626 km (389 miles) |
| Best sub-section | Fethiye (km 195) to Antalya (km 488), about 293 km (182 miles) |
| Part of | European route E90 between Nizip and Cizre |
| Layout | Two lanes on the Lycian coast, wider and faster east of Antalya |
| Best months | April to June and September to October, as of August 2026 |
| Time on the coast | 3–4 days Datça to Alanya with stops |
Open the Fethiye–Kaş–Antalya run in Google Maps and send it to your navigation before you leave.
Datça, Marmaris and the opening run
The western end is a peninsula road rather than a coast road. Datça sits at the tip, 69 km (43 miles) west of Marmaris, and the run between them is a narrow ridge road with water on both sides — worth riding out and back purely for what it is. Marmaris itself is a large resort town and the D.400 through it is busy.
East from Marmaris the road turns inland through Muğla, Köyceğiz and Ortaca before returning to the coast at Dalaman and Fethiye. This stretch is pleasant rather than special; pine forest, agriculture, easy corners. It is the approach, not the event.
Fethiye to Kaş, the good part
From Fethiye the D.400 climbs onto the Lycian coast and becomes the road people mean. Between Fethiye and Kalkan, 80 km (50 miles) apart, it runs high above the sea with long sightlines, consistent radii and a surface that is generally excellent. There are laybys at the right places. The sea is a colour that does not photograph accurately.
Kalkan to Kaş is only 26 km (16 miles) and is the single best section on the whole road: tighter, closer to the water, with the Greek island of Kastellorizo sitting offshore. Kaş is the natural overnight stop — a small harbour town rather than a resort strip, with the road running above it. Riders consistently rate this 300 km (186 mile) stretch from Fethiye to Antalya as the reason to come to Turkey at all.
Demre, Finike, Kemer and the drop into Antalya
Past Kaş the road drops to sea level at Demre, 47 km (29 miles) further on, where greenhouse agriculture covers the coastal plain and the riding flattens out. Finike and Kumluca follow, and then the D.400 climbs again for the 52 km (32 mile) run to Kemer, which is the second great section: forest, cliffs and the Beydağları mountains dropping straight into the water on your right.
Kemer to Antalya is 42 km (26 miles) of increasingly urban road. Antalya is a city of over a million people and the D.400 goes straight through it as Dumlupınar Bulvarı; there is no scenic way through. Plan to arrive outside rush hour, or use the ring road and rejoin east of the city.
East of Antalya
The coast continues, but the balance shifts. Antalya to Alanya is 138 km (86 miles) of resort strip — dual carriageway in places, heavily built up, fast rather than interesting. Beyond Alanya the road empties out again through Gazipaşa, Anamur and Bozyazı, and this eastern stretch is genuinely good riding with much less traffic than the Lycian coast, if less dramatic. The Boğsak tunnel section in Mersin province marks where the road starts turning into a trunk route.
From Mersin and Adana onwards the D.400 heads inland and east through Gaziantep, Şanlıurfa and eventually Hakkâri towards the Iranian border. That is a serious undertaking with its own planning requirements, and riders considering it should consult their own government's current travel advice for the south-eastern provinces before committing to a route rather than treating it as more of the same road.
Season, paperwork, fuel and traffic
Season. The Mediterranean coast is hot. July and August combine peak temperatures with peak tourist traffic, which is the worst possible mix on a two-lane cliff road. April to June and September to October are the riding months: warm sea, manageable heat, thinner traffic. Winter is mild at sea level and wet, and the inland roads over the Taurus can carry snow. Verified as of August 2026; check forecasts before you commit.
Vehicle paperwork. Türkiye does not appear on the commonly published lists of countries requiring a Carnet de Passages en Douane. Foreign vehicles enter under Turkish customs' temporary importation rules, with a maximum accompanied stay of 730 days, and the Turkish Touring and Automobile Association (TURING) issues a temporary entrance document for private vehicles. The rules on whose name a vehicle must be registered in are stricter than in the EU and have caused refusals at land borders, so check the Ministry of Trade guidance at trade.gov.tr and TURING at turing.tr before you arrive. Carry registration, licence, passport and insurance valid in Türkiye — European green card cover does not automatically extend to the whole country, so confirm with your insurer.
Visas. Entry requirements depend on nationality and change. Use the official e-visa portal or a Turkish mission, and check passport validity rules.
Fuel. Easy. Every town along the coast has stations, most are attended, most take cards, and the longest gap on the Lycian section is comfortably under a normal tank. The one place to pay attention is the Datça peninsula, where you should fill before riding out to the tip.
Traffic and enforcement. Speed enforcement is active and cameras are common on the intercity roads. The practical hazards are tour coaches on the cliff sections, minibuses stopping without warning, and in resort areas a lot of people on scooters with limited experience. Surfaces are good but the tarmac gets slippery in the first rain after a dry spell. Riding at night on the mountain sections is best avoided.
Gear notes for a long hot coast run
Heat is the thing to plan around. Air temperature in the high thirties over black tarmac moves tyre pressures a long way between a cool morning start and a mid-afternoon stop, and a loaded touring bike feels it — our tyre pressure guide covers what that does to grip and a TPMS sensor keeps the number in front of you rather than in your head. Coverage along the coast is generally decent but drops in the mountain sections between Kaş and Kemer and on the empty stretch east of Alanya, so having the corridor downloaded for offline motorcycle navigation is worth the setup time; the problems with phone-only navigation get worse in this kind of heat, since phones throttle in direct sun on a bar mount. If you are pairing the coast with the interior, our Cappadocia guide covers the obvious inland leg, and a bi-directional fast charger handles the pension sockets that are never where you want them.
FAQ
Which part of the D.400 should I ride?
Fethiye to Antalya, about 293 km (182 miles), with the Kalkan–Kaş stretch as the highlight. If you have more time, extend west to Datça and east past Alanya to Anamur.
How long is the whole D.400?
2,057 km (1,278 miles) from Datça to Esendere on the Iranian border. Almost nobody rides all of it in one trip, and the eastern half is a different kind of journey from the coast.
When should I avoid it?
July and August. The combination of peak heat and peak holiday traffic on a two-lane cliff road takes most of the pleasure out of it. April to June and September to October are much better.
Do I need a carnet for Türkiye?
No — Türkiye is not on the commonly published carnet-required lists. Vehicles enter under customs temporary importation rules with a 730-day maximum for accompanied vehicles. Confirm the current requirements at trade.gov.tr and turing.tr, and make sure the vehicle is registered in your own name.
Is the road surface good?
Generally very good on the coastal section, with well-maintained tarmac and proper barriers on the cliff stretches. The usual caution applies to the first rain after a long dry spell, and to gravel washed onto the road at side junctions in the mountains.
