Northern Thailand begins where the flat rice-growing countryside above Bangkok rises slowly to the mountains that border Myanmar and Laos. It's a vast region of Thailand, about the size of the state of Kentucky, that bears striking geographic and cultural differences from the south. The mountains that are the distinguishing feature of the north contribute to the region's distinctly different character, protecting its mostly rural people, and particularly its hill tribes, from too rapid an advance of outside influences.
The north has its own language ("Muang"), cuisine, and traditional beliefs and rituals (many of them animist) and a sturdy architectural style that has come to be known as Lanna ("a million rice fields"). All these features contrast strikingly with the distinguishing features of the rest of Thailand, where the strict practices of Buddhism have a greater hold on the people and where western influences have made greater inroads.
Although Chiang Mai is the natural capital of northern Thailand it's not the only city of this region deserving inclusion in any Thailand itinerary; Chiang Rai, Chiang Saen, Mae Hong Son, Phrae, and Nan have enough attractions, particularly historic temples, to make at least overnight visits worthwhile. The ancient city of Sukhothai, with its stunning ensemble of temple ruins, is a stand-alone destination in its own right but can be easily integrated into a tour of the north. The mountains and forested uplands that separate these fascinating cities are studded with simple national park lodges and luxury resorts, hot-water spas, elephant camps—the list is endless.
Chiang Rai is a particularly suitable base for exploring the region further—either on treks to the hill tribe villages that dot the mountainsides or on shorter jaunts by elephant. The fast-flowing mountain rivers offer ideal white-water rafting and canoeing. The truly adventurous may want to head for one of the region's national parks, which offer overnight accommodations and the services of guides.
From Chiang Rai, circular routes run through the city's upland surroundings and deep into more remote mountains, where descendants of Chinese soldiers who fled after the Communist takeover of their country grow coffee and tea. Nan, tucked away in the mountainous corner bordering Laos; and Mae Hong Son and Mae Sariang, where Myanmar lies just over the nearest range. The so-called Mae Hong Son Loop, a spectacular road starting and ending in Chiang Mai, runs through a small market town, Pai, that has developed over the years into a major tourist destination. First discovered by backpackers doing the "Loop," the town's simple guesthouses are now making way for smart resorts designed for Bangkok businesspeople seeking a quiet weekend in the north.