3D print St. Petersburg
Built on a river delta and planned from the start as a European capital, St. Petersburg's historic core is unusually flat, wide, and regular — good conditions for a legible print.
Draw around Palace Square and you get the Winter Palace, the sweep of the Admiralty embankment, and the Neva itself, wide enough that the water reconstruction (built from OpenStreetMap's coastline data, the same as any river or sea in the dataset) reads clearly even at a small scale. The historic center's low, even roofline — a legacy of a height limit that held for most of the city's history — means individual streets and courtyards stay readable instead of disappearing under a few towers.
The Winter Palace's roof silhouette and St. Isaac's Cathedral's gilded dome both print well as details even at this small scale — the historic center's height limit keeps them the tallest things around, so they stay legible rather than getting crowded out.