| Kailu County | |
| Other Name: | K'ai-lu |
| Settlement Type: | County |
| Image Map1: | Location of Tongliao Prefecture within Inner Mongolia (China).svg |
| Map Caption1: | Tongliao in Inner Mongolia |
| Pushpin Map: | China Inner Mongolia#China |
| Pushpin Label: | Kailu |
| Pushpin Map Caption: | Location in Inner Mongolia |
| Subdivision Type: | Country |
| Subdivision Name: | China |
| Subdivision Type1: | Autonomous region |
| Subdivision Name1: | Inner Mongolia |
| Subdivision Type2: | Prefecture-level city |
| Subdivision Name2: | Tongliao |
| Seat Type: | County seat |
| Seat: | Kailu Town |
| Area Total Km2: | 4,353.2 |
| Population As Of: | 2020 |
| Population Footnotes: | [1] |
| Population Total: | 313,364 |
| Population Density Km2: | auto |
| Timezone: | China Standard |
| Utc Offset: | +8 |
| Coordinates: | 43.601°N 121.319°W |
| Postal Code Type: | Postal code |
| Mon: | Кайлу шянь |
| Monr: | Ḵayilü siyan |
| Order: | st |
| S: | 开鲁县 |
| T: | 開魯縣 |
| P: | Kāilǔ Xiàn |
Kailu County (Mongolian: ;) is a county in the east of Inner Mongolia, China. It is under the administration of Tongliao City, to the east, and China National Highway 303 passes through it.
As the traditional seat of Ar Khorchin, East Jaruud and West Jaruud, the 3 areas are abbreviated in Chinese as the 3 R's since each contains the word R transcribed as "LU" in Chinese. The 3 R's was then known as the 3 Lu's as well. In 1905, with the slogan of developing the 3 R's (開發三魯), the city took the name of such abbreviation and was named 開魯 (KAI LU).
Kailu County is made up of 10 towns.
| Name | Simplified Chinese | Hanyu Pinyin | Mongolian (Hudum Script) | Mongolian (Cyrillic) | Administrative division code |
|---|---|---|---|---|---|
| Towns | |||||
| Kailu Town | Chinese: 开鲁镇 | Mongolian: Кайл балгас | 150523100 | ||
| Dayushu Town | Chinese: 大榆树镇 | Mongolian: Да юй шуу балгас | 150523101 | ||
| Heilongba Town | Chinese: 黑龙坝镇 | Mongolian: Гей лүн ба балгас | 150523102 | ||
| Maixin Town | Chinese: 麦新镇 | Mongolian: Майшин балгас | 150523103 | ||
| Ih Tal Town | Chinese: 义和塔拉镇 | Mongolian: Ихдэлээ балгас | 150523104 | ||
| Jianhua Town | Chinese: 建华镇 | Mongolian: Жаанхуа балгас | 150523105 | ||
| Xiaojieji Town | Chinese: 小街基镇 | Mongolian: Шяо жье жий балгас | 150523106 | ||
| Dongfeng Town | Chinese: 东风镇 | Mongolian: Дүн фен балгас | 150523107 | ||
| Jargalangt Town | Chinese: 吉日嘎郎吐镇 | Mongolian: Жаргалант балгас | 150523108 | ||
| Donglai Town | Chinese: 东来镇 | Mongolian: Дүн лай балгас | 150523109 | ||
Kailu County features a cold semi-arid climate (Köppen BSk), marked by long, very cold and dry winters, hot, somewhat humid summers, and strong winds, especially in spring. The monthly daily mean temperature in January, the coldest month, is NaN°C, and in July, the warmest month, 24.2°C, with the annual mean at 7°C. The annual precipitation is 327.4mm, with nearly half of it falling in July and August alone.