Hisar (Fortress) is a family of short, High to medium air defense surface-to-air missile systems being developed by Roketsan and Aselsan since 2007.

On 18 April 2007, the Turkish Presidency of Defense Industries issued a request for information to international and domestic defence companies to meet a low to medium altitude air defense requirements under Turkey's Low Altitude Air Defence Missile System (T-LALADMIS) programme (Alçak İrtifa Hava Savunma Füze Sistemi in Turkish).

[22] On 3 March 2020, Turkey said the system would be deployed in Syria's Idlib province as part of Operation Spring Shield.

Hisar-A has dual pulse solid propellant rocket motor, making it effective against highly maneuverable air targets, although the 5 km maximum engagement altitude is a limitation.

While the missile did not achieve a direct hit, the warhead was detonated by the proximity fuse, when it was passing the target.

[citation needed] Hisar-O (Turkish: Orta İrtifa Hava Savunma Füze Sistemi) is a vertically launched medium-range SAM system mounted on a Mercedes-Benz Zetros chassis.

[8][40] Hisar-O missile system is very similar to the Hisar-A family, and uses same type of IIR seeker, RF link, proximity fuse and dual-pulse rocket motor.

Another improvement is the installation of Aselsan's Kalkan phased array 3D search and track radar on the launcher vehicle.

[5][6][7][8] The system's general features also include management and distribution of command and control information, air defense mission planning at the battery and battalion levels, multiple engagement and successive firing, data links for midcourse guidance, integrated air picture generation, operational capabilities in the day, at night and in adverse weather conditions, a global positioning system (GPS) and navigation, remote control, wired or wireless communication between systems, 360° effective area with the capability of vertical launch, Multi-Target Multi-Radar fusion and embedded simulation, identification friend or foe (IFF), modular structure, hybrid control system.

[44][45] Indonesia has signed a contract for the purchase of a variant of the Hisar-O and SİPER surface-to-air missile system from Turkish defense company Roketsan at Indo Defence 2022, the system is known as Trisula-O and Trisula-U, and its made specifically for Indonesia's demands, request, and needs.