Distance of Zheng He's Voyage from Nanjing to Mecca

The source material does not provide the exact distance of Zheng He's journey from Nanjing to Mecca along the most direct sea route. However, historical records indicate that Zheng He's treasure fleets traveled vast distances across the Indian Ocean, reaching the Arabian Peninsula and the Red Sea during the early 15th century. The voyages demonstrated remarkable navigational capability and connected China with distant regions.

For precise nautical mileage, specialized maritime histories or academic studies of the Ming treasure voyages would be required.