Which microstate has a national railway only about 300 metres long?

Vatican City has the national railway that is only about 300 metres long within its territory.

The Vatican Railway connects Vatican City with Italy’s rail network through Roma San Pietro station. Although the full route, including the Italian section, is about 1.27 kilometres, only roughly 300 metres of track lies inside Vatican City, making it the world’s shortest national railway system.

The railway was provided for in the Lateran Treaty of 1929, which established Vatican City and guaranteed its connection to Italy. Construction took place during the pontificate of Pope Pius XI, and the line and station were ready for use by 1934. The grand station building was designed to suit the symbolic setting near St. Peter’s Basilica.

The line was never the regular papal transport system many people imagine. It has mainly carried freight, with occasional special passenger and pilgrimage services. Since 2015, tourist trains have also operated between Vatican City and Castel Gandolfo.