National Transportation Day, or Hari Perhubungan Nasional, is observed in Indonesia every September 17. Established in 1971 by then Minister of Transportation Frans Seda, the day aims to unify various stakeholders in the transportation sector, including the Ministry of Transportation and regional governments, to foster collaboration and innovation. The significance of this day lies in Indonesia's unique geography as the largest archipelagic state, comprising over 17,000 islands, making an efficient transportation system crucial for economic and territorial integrity. Celebrations typically focus on enhancing the coordination among transportation modes, which include air, water, and land transport, ensuring they complement rather than compete with each other. The event highlights the importance of meeting five key criteria for the transportation system: low cost, safety, speed, convenience, and punctuality.