Musée des Timbres et des Monnaies

This compact museum holds the personal stamp and coin collections of Prince Rainier III, who founded it in 1950 — making it one of the world's top numismatic institutions. You'll find rare Monégasque stamps and coins that trace centuries of the principality's history, all in one focused, surprisingly absorbing collection. It's a niche gem, but if you have any interest in history, royalty, or miniature artistry, it genuinely delivers.