Extremely mountainous and in some areas still blanketed in teak forests, travellers are attracted both to the cooler climate and the very popular trekking opportunities that can be experienced in the far north. The hills and mountains are populated by a great number of ethnic minority groups -- Akha, Lisu, Hmong, Karen and Lahu to name a few -- many of whom have traditional clothing, culture and language that are totally foreign not only to travellers but also to other Thais. The opportunity to go trekking in the north, spending an evening or two in a minority village is, for many, one of the most memorable experiences of their trip to Thailand.