Qasr-e-Shirin (Ghasr-e Shirin) lies at a distance of 692 km. from Tehran, and is located to the northwest of Kermanshah. The climate of this city is warm and from this point of view it is distinctive from the other townships of the province.
Qasr-e-Shirin is one of the ancient cities of Iran related to the Khosrow Parviz era. It was thriving during the Achaemenian period. Around the present city the ruins of the ancient Qasr-e-Shirin, has been remained together with a collection of demolished stone and walls. It is said that during the rule of Khosrow Parviz there was a large garden with beautiful palaces. Out of which the most famous were Khosrow and Shirin Palaces.
Qasr-e-Shirin till 1270 AH. was a small town. But in the World War I became the border town for the German and Ottoman soldiers from one hand and for English and Russian soldiers on the other hand. During the Iran-Iraq war Qasr-e-Shirin was demolished, but after the conclusion of the war it was renovated. Now this city has expanded and has changed to attractive and large area.