The Lanna region is a former kingdom in the area of modern-day Northern Thailand that also once extended into Myanmar, Laos and China. Currently, Lanna culture is used as a selling point for tourism to Northern Thailand, but there are problems with the way tourism routes are designed and packaged. This paper aims to promote the architectural value of Lanna culture through the development of tourism routes. The qualitative investigation assesses existing Lanna tourist routes in Northern Thailand and develops guidelines for the development of cultural tourism in the region. Initial research led to the identification of 35 sites for in-depth evaluation. Data was gathered by document research, field evaluation and interviews following criteria co-developed by Chulalongkorn University and the Department of Tourism (2007). Findings indicated that destinations in Northern Thailand are of a good standard but should be developed in terms of tourism support and management. The researchers produced guidelines for the development of individual attractions and designed cultural routes according to provincial boundaries and periodic themes.