Stand on the shore anywhere near Kronstadt and you are looking at a dredged highway hidden under the water. The Maritime Channel, the Sea Canal of St Petersburg, was cut through the shallow Neva Bay in the late nineteenth century, opening in 1885, so that large ships could reach the city's port directly instead of unloading at Kronstadt. Before it existed, the bay was too shallow for anything but small vessels, and cargo had to be transferred to lighters, a slow and expensive business. The channel runs for around thirty kilometres from the open gulf to the mouth of the Neva, marked by buoys and lights, and it remains the main artery for ships entering the city.
The island of Kotlin, with the naval town of Kronstadt, sits at the western end of the bay. Peter the Great founded the fortress there in the early eighteenth century to protect his new capital from the Swedish fleet, and it became the base of the Baltic Fleet. The Naval Cathedral of St Nicholas, completed in 1913, dominates the town with its huge dome, and the harbours and forts around the island tell three centuries of naval history.
Today Kronstadt is connected to both shores of the gulf by the flood protection barrier, a chain of dams and sluices completed in 2011 to protect St Petersburg from the storm surges that have flooded the city repeatedly over its history. The ring road runs along the barrier, crossing the main shipping passage through a tunnel beneath it. Riding across is a strange experience: a motorway in the middle of the sea, with water on both sides and the wind blowing hard and constantly. Crosswinds can be strong, so hold on.
The landscape is flat and open, all sky and water. Seabirds gather on the rocks of the old forts, and in winter the bay freezes and fishermen walk out on the ice. The light changes constantly, from steel grey to brilliant blue, and sunsets over the gulf in summer last for hours.
Kronstadt has fuel, shops and cafés, and the towns on the southern shore, Lomonosov and Peterhof, are close. As for any trip in Russia at present, check entry requirements and travel advice carefully before you go.