Veniamin Kaverin's The Two Captains is set in Pskov (the book's "Ensk"), Moscow, Leningrad and the Arctic, following Sanya, a mute boy who grows into an Arctic pilot and sets out to prove what happened to a lost polar expedition.
The route follows the book from a flooded yard in Pskov to the orphanages of Moscow, the Leningrad blockade, the archipelago of Severnaya Zemlya and Polyarny's Square of Two Captains. Moscow, Leningrad and Severnaya Zemlya are city- or region-level pins, since the book names no exact addresses there.
Beatrix Potter's tales are set in the real Lake District: Mr McGregor's garden at Lingholm near Derwentwater, Owl Island on St Herbert's Island, Mrs Tiggy-Winkle's home on Catbells, and the village and farm of Near Sawrey, including Hill Top.
The route follows five places from Peter Rabbit in 1901 to the Hill Top tales of 1907 and 1908, moving from the shores of Derwentwater to the house Potter bought in 1905. Some pins mark an area, not a single spot.