Editing Northern Thailand (section)

==Geography==
{{see also|Mae Chan Fault}}
North Thailand is bound by the [[Salween River]] in the west and the [[Mekong]] in the east. The basins of rivers [[Ping River|Ping]], [[Wang River|Wang]], [[Yom River|Yom]], and [[Nan River|Nan]], all tributaries of the [[Chao Phraya River]], in the central part run from north to south and are mostly very wide. The basins cut across the mountains of two great ranges, the [[Thanon Range]] in the western part and the [[Phi Pan Nam]] in the eastern. Their elevations are generally moderate, a little above {{convert|2,000.|m}} for the highest summits. Although formerly forested, many of these mountains are now denuded.<ref>[http://rainforests.mongabay.com/deforestation/archive/Thailand.htm Forest data: Thailand Deforestation Rates]</ref>

Parallel mountain ranges extend from the [[Daen Lao Range]], in the southern region of the [[Shan Hills]], in a north–south direction, the [[Dawna Range]] forming the western border of Thailand between [[Mae Hong Son]] and the [[Salween River]].<ref>[http://www1.mod.go.th/heritage/nation/geography/geo3.htm Northern Thailand] {{webarchive|url=https://web.archive.org/web/20120128091643/http://www1.mod.go.th/heritage/nation/geography/geo3.htm |date=2012-01-28 }}</ref> To the east the [[Thanon Thong Chai Range]], the [[Khun Tan Range]], the [[Phi Pan Nam Range]], as well as the western part of the [[Luang Prabang Range]], form the natural region of the Thai highlands together with the former.<ref>ดร.กระมล ทองธรรมชาติ และคณะ, สังคมศึกษา ศาสนาและวัฒนธรรม ม.1, สำนักพิมพ์ อักษรเจริญทัศน์ อจท. จำกัด, 2548, หน้า 24-25</ref>

The high mountains are incised by steep river valleys and upland areas that border the central plain. A series of rivers, including the [[Nan River|Nan]], [[Ping River|Ping]], [[Wang River|Wang]], [[Yom River|Yom]], and [[Nan River|Nan]], flow southwards through mountain valleys and join to form the [[Chao Phraya River|Chao Phraya]] in [[Nakhon Sawan Province]] in the central region. [[Sirikit Dam]] is on the Nan River in Uttaradit Province. The northeastern part is drained by rivers flowing into the [[Mekong]] basin, like the [[Kok River|Kok]] and [[Ing River|Ing]].

The four-region system includes the northern parts of the [[Central Thailand|central plain]] as well as some mountainous areas bordering the western and the northeastern limits. The total forest area is {{convert|90,228|km²|abbr=on}} or 52.5 percent of this four-region area.<ref name="RFD"/>

===National parks===
{{main|List of national parks of Thailand}}
Within the northern region there are some sixty [[List of protected areas of Thailand#National parks in the Thai highlands|national parks]]. Chiang Mai Province has nine national parks of which [[Doi Inthanon National Park]] with the country's highest mountain and [[Op Luang National Park]] have a scenic river canyon, waterfalls, and caves. [[Doi Khun Tan National Park]], which is located midway between the two provincial capitals of province Lampang and Lamphun, is best known for Thailand's longest railroad tunnel, which is {{convert|1,352|m}} long. [[Doi Phu Kha National Park]] in province Nan is northern Thailand's largest national park.