Heriz is situated in the northwestern part of Iran (Persia). Though the term covers Hand knotted rugs of numerous small villages in the area, the most beautiful Rugs were woven in Heriz itself For the last 100 years, the Heriz carpet designs have basically remained the same, with only small variations in color pallets and density of the design. The late 19th Century Rug (so called Serapis) was of fewer details and softer colors and with time designs became denser with added jewel tone color pallets. The revival of the carpet industry in the late 19th Century was based on the demand of the Western markets, with America in particular. Weavers in Heriz hand knotted were asked to make carpets inspired by the Fereghan Sarouks of higher cost for consumers of more limited budgets. Even though Sarouk carpets changed style later on, Heriz weavers stayed with the geometric pattern till now. However, Heriz was also a center of production of some of the best handmade carpets with both geometric and curvilinear floral patterns. A special heirloom wash produces the subtle color variations that give rugs their distinctive antique look.