To the Russian navy, Kronstadt is the fortress island of Kotlin in the eastern Gulf of Finland, and the forts scattered across the water around it were built to stop any enemy from approaching St Petersburg by sea.
Lomonosov, the town to the west, was once Oranienbaum, the estate of Prince Menshikov, Peter's favourite, and later of Peter III. During the siege of Leningrad in 1941 to 1944 a small stretch of this coast, known as the Oranienbaum Bridgehead, was held by Soviet troops against the German army, cut off from the city by the sea and supplied by ships across the gulf. The memory of that struggle is strong here, and monuments dot the roads. The route that mentions Oranienbaum Springboard refers to this episode.
The ride is flat and coastal. The road follows the shore through pine and birch woods, with glimpses of the water and the low outline of Kronstadt on the horizon, and the surface is mostly smooth. Traffic is heavy near the towns and light between them. In winter the Gulf freezes and the forts stand in a field of white, while in summer the white nights give a long, soft twilight. Wind off the water can be strong.
Fuel is easiest in Kronstadt or Lomonosov, both towns of more than forty thousand people, with garages and shops. In Lomonosov you can visit the palace-park ensemble of Oranienbaum, which includes the Chinese Palace, and a café or two serve simple meals. Check current access rules for any coastal area before you go, since parts of this coast are restricted, and carry your documents.