Sandi Museum, Cryptography museum in Kotabaru, Yogyakarta, Indonesia

Sandi Museum is a building in Gondokusuman that displays encryption tools, cipher machines, and communication methods across two floors. The exhibition is organized into nine separate rooms that showcase different aspects of cryptographic technology and practice.

Museum Sandi was initiated in 2006 by Nachrowi Ramli, head of the National Cipher Agency, and Sri Sultan Hamengku Buwono X, governor of Yogyakarta. It opened on 29 July 2008 on the ground floor of the Museum Perjuangan Yogyakarta, and that date is now its anniversary. On 29 January 2014 it moved to a Dutch-architectured heritage building on Jalan Faridan Muridan Noto 21, which had housed the Ministry of Foreign Affairs in 1947.

The museum honors Dr. Roebiono Kertopati's work in developing encryption methods that played a role during Indonesia's independence movement. His contributions shaped how the country approaches secure communication and coding techniques.

Access to the museum is straightforward, with rooms well distributed across two floors and no significant obstacles to navigate. Signs at the entrance and throughout the corridors guide visitors easily through all nine exhibition spaces.

The collection includes original cipher machines from the United States, Vatican City, and Germany alongside devices engineered in Indonesia. This international mix reveals how different nations developed similar encryption technology during the twentieth century.