The Russian route M4 is a major trunk road

Trunk road

A trunk road, trunk highway, or strategic road is a major road—usually connecting two or more cities, ports, airports, and other things.—which is the recommended route for long-distance and freight traffic...

 that links Moscow

Moscow

Moscow is the capital, the most populous city, and the most populous federal subject of Russia. The city is a major political, economic, cultural, scientific, religious, financial, educational, and transportation centre of Russia and the continent...

 to Rostov-on-the-Don. Its length is 1164 kilometres.

The route starts at the Moscow Ring Road (as Kashira Highway) and runs south, passing west of Vidnoye

Vidnoye

Vidnoye is a town and the administrative center of Leninsky District of Moscow Oblast, Russia, situated south of Moscow city limits. Population:...

, east of Domodedovo, west of Kashira

Kashira

Kashira is a town and the administrative center of Kashirsky District of Moscow Oblast, Russia, located on the Oka River south of Moscow. Population:...

 and Stupino

Stupino

Stupino is a town and the administrative center of Stupinsky District of Moscow Oblast, Russia, located on the Oka River south of Moscow. Population:...

, where the Caspian Highway branches off to the east. The Don Highway continues across Tula Oblast

Tula Oblast

Tula Oblast is a federal subject of Russia with its present borders formed on September 26, 1937. Its administrative center is the city of Tula. The oblast has an area of and a population of 1,553,874...

 west of Venev, through Bogoroditsk

Bogoroditsk

Bogoroditsk is a town and the administrative center of Bogoroditsky District of Tula Oblast, Russia, located on the Upyorta River, a tributary of the Upa. Population:...

 and Yefremov

Yefremov (town)

Yefremov is a town and the administrative center of Yefremovsky District of Tula Oblast, Russia, located on the Krasivaya Mecha River , south of Tula. Population:...

, then across Lipetsk Oblast

Lipetsk Oblast

Lipetsk Oblast is a federal subject of Russia which was formed on January 6, 1954. Its administrative center is the city of Lipetsk...

, passing through Yelets

Yelets

Yelets is a city in Lipetsk Oblast, Russia, situated on the Sosna River, which is a tributary of the Don. Population: -History:Yelets is the oldest center of the Central Black Earth Region. It is mentioned in historical documents as far back as 1146, when it belonged to the Princes of Ryazan...

 and Zadonsk

Zadonsk

Zadonsk is a town and the administrative center of Zadonsky District of Lipetsk Oblast, Russia, located southwest of Lipetsk, on the left bank of the Don River, from which it takes its name...

, and then across Voronezh Oblast

Voronezh Oblast

Voronezh Oblast is a federal subject of Russia . It was established on June 13, 1934.-Main rivers:*Don*Voronezh*Bityug*Khopyor-Economy:...

, bypassing Voronezh

Voronezh

Voronezh is a city in southwestern Russia, the administrative center of Voronezh Oblast. It is located on both sides of the Voronezh River, away from where it flows into the Don. It is an operating center of the Southeastern Railway , as well as the center of the Don Highway...

 and Boguchar

Boguchar

Boguchar is a town in Voronezh Oblast, Russia, located on the Boguchar River south of Voronezh. Population: Town status was granted to it in 1779....

. After crossing the Don River

Don River (Russia)

The Don River is one of the major rivers of Russia. It rises in the town of Novomoskovsk 60 kilometres southeast from Tula, southeast of Moscow, and flows for a distance of about 1,950 kilometres to the Sea of Azov....

 near Rostov, the road continues even further south to Krasnodar

Krasnodar

Krasnodar is a city in Southern Russia, located on the Kuban River about northeast of the Black Sea port of Novorossiysk. It is the administrative center of Krasnodar Krai . Population: -Name:...

 and Novorossiysk

Novorossiysk

Novorossiysk is a city in Krasnodar Krai, Russia. It is the country's main port on the Black Sea and the leading Russian port for importing grain. It is one of the few cities honored with the title of the Hero City. Population: -History:...

.

The Don Highway, extensively upgraded and widened in the 2000s, is an artery connecting Moscow with Southern Russia

Southern Federal District

Southern Federal District is one of the eight federal districts of Russia. Its territory lies mostly on the Pontic-Caspian steppe. Its population was 13,856,700 according to the 2010 Census, living on an area of...

. In the summer months, the road suffers from heavy traffic congestion caused by summer vacationers travelling to the Black Sea

Black Sea

The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

 resorts like Sochi

Sochi

Sochi is a city in Krasnodar Krai, Russia, situated just north of Russia's border with the de facto independent republic of Abkhazia, on the Black Sea coast. Greater Sochi sprawls for along the shores of the Black Sea near the Caucasus Mountains...

and by lorries transporting fruit from the southern provinces to the heavily populated areas of Central and Northern Russia.