The motorway is located in the Yugozapaden area in South West Bulgaria, and follows the route Sofia-Pernik-Dupnitsa-Blagoevgrad-Sandanski to Kulata on the border with in Greece.

The Struma motorway forms a connection between Sofia and Kulata at the Bulgaria-Greece border with a total planned length of 172.8 km.

[8] Due to its complexity and high construction cost lot 3 has been set back to the 2014–2020 financial period and only a conceptual design had been drafted.

Due to the mountain relief in this part of the country an economically viable motorway can only cut across the Kresna Gorge, a protected Natura 2000 site[11] and a habitat of many flora and fauna endangered species.

Non-governmental organizations, including institutions such as Friends of the Earth Europe (FoEE), Balkani Wildlife Society, CEE Bankwatch Network, Green Policy Institute, and Centre for Environmental Information and Education, have all expressed concern through petitions, protests and studies, insisting the motorway must bypass the gorge in order to avoid further harm.

The plan was met with an instant and stiff opposition from the local construction companies, and had since been shelved also due to concerns about the environmental impact of the construction works and the deposition of the excavated material from the tunnel, as well as worries about ballooning maintenance costs of the completed tunnel.

[13] The plan was also opposed by hundreds small business owners whose livelihood would be affected by the decommissioning of portions of I-1 road and land expropriation.

The Liulyn Motorway was partially financed by The Instrument for Structural Policies for Pre-Accession (ISPA) and the Daskalovo-Dolna Dikanya section of the highway received a loan from the European Investment Bank (EIB).

[17] On 8 August 2006, a contract for the construction of the motorway was signed with the Turkish consortium Mapa Cengiz for 137,381,785 euro.

On 23 November 2021, a North Macedonian bus carrying 52 passengers and 2 bus drivers crashed into a barrier on the motorway near the village of Bosnek, 44.2 km south from Sofia, while going back to the North Macedonian capital of Skopje from a weekend trip in Istanbul.

45 people, including 12 children, died in the crash, and 7 were hospitalized after escaping through the windows of the burning bus.