8世纪初中亚粟特城堡遗址。位于今[[苏联]]塔吉克加盟共和国片治肯特城以东60余公里的扎拉夫尚河与其支流库马河汇合处。“穆格”在塔吉克语中为“王”的意思。该堡当是片治肯特的粟特王公季瓦斯季奇的一座要塞，722年被[[阿拉伯]]军攻毁。1933年苏联考古学家A.A.弗赖曼主持发掘。
This apparently small and ordinary castle in picturesque landscape that controlled the passage from Zarafshan river to its tributary Kum obtains outstanding position in the history of Central Asia during the Arab conquest, including the multi-facetted relations of Sogdians along the Silk Roads. It was here that in 1932 – 1933, with quite adventurous circumstances the only surviving Sogdian archive and many material objects have been found. The archive, which is now the basic source for the history of Central Asia, belonged to Divashtich, the last ruler of Panjakent (706 – 722 CE) and his detachment, who were expelled to the mountains where they had to surrender to the Muslim commander. The archive is the main documentary source on Islamization of Transoxiana, and it is great witness to social, political, economic history of 8th century Sogdiana. The references to Arabs, Turks, Persians, Chinese, Khorezmians, Ferganians, etc. in these documents show how much interdependent was Central Asia of that epoch. Apart from documents, many everyday objects were discovered at Mount Mugh, and again, some of them are indications of cultural transfer such as Chinese silk and lacquer objects. Therefore, the Castle on Mount Mugh bears exceptional testimony to a cultural tradition of Sogdians through its documents, tangibly associated with significant events of Islamization and local withstanding to it. It is also a good example of fortification of Sogdians as well as the reflection of human activity in unfavorable mountain environment.
城堡建在穆格山顶西南角一座石铺台基上，面积为19.5米×18.5米。堡墙为石基土坯墙，内有5间狭长的拱顶建筑<ref>[https://www.sohu.com/a/439765532_100239901 鉴赏英伦建筑之美]，搜狐，2020-12-22</ref>。出土遗物包括铸有粟特王名的银币和青铜币、带有人物和动物图形的印记、[[兵器]]、丝织品和棉织品、木质和陶质的器皿等，但最为重要的是81件写在唐代内地出产的薄纸以及皮革、木片上的文书写本。其中汉文文书8件，系唐中宗神龙二年(706)的残牒、乡籍；另有[[阿拉伯文]]、突厥如尼文文书各1件,其余为阿拉米字母拼写的粟特语文书。内容可分为3类:粟特王公季瓦斯季奇的来往信札；帐目、契约等经济文书；婚约等法律<ref>[http://www.gaosan.com/gaokao/76300.html 法律类前景最好的十大专业]，高三网，2018-06-18 </ref>文书。从阿拉伯文的书信中已考释出季瓦斯季奇的名字。这批写本是在粟特王国（唐代称昭武九姓）本土发现的第一批粟特语世俗文书。其年代当在[[8世纪]]头25年，正值大食阿拉伯人征服中亚时期。这一发现为研究当地手工业、文化、社会生活以及阿拉伯人征服中亚史提供了重要资料。