The O 3500 was the first Mercedes-Benz bus designed in the post-war period. It still featured the conventional cab-behind-engine configuration and was offered in several variants as a regular-service bus and touring coach. The exhibited vehicle is a luxury coach with glazed roof edges of the type used for tourist travel to Italy in the 1950s.

• Cylinders 6
• Displacement 280 cu in
• Output 90 hp (66 kW)
• at engine speed 2800/min
• Top speed 51 mph
• Seats 29
• Production period 1949-1955
• Units produced 2644