The research aims to 1) promote historic and cultural tourism at royal temples in Ayutthaya province; and to 2) identify ways of promoting cultural tourism sustainably. The research methodology is mixed-method. The quantitative data was collected from approximately 400 Thai tourists by means of questionnaires. The qualitative data was collected by means of interviews with 8 tourism stakeholders in Ayutthaya province. Data were analyzed to identify the frequency percentage mean (x̅) and standard deviation (S.D.) using SPSS. The research found that Thai tourists and tourism stakeholders support measures to develop Royal temples in Ayutthaya including: 1)Wat Phra Sri San Phet; 2) Wat Panan Cheng Worawiharn; 3) Wat Na Phra Maen; 4) Wat Kasattra Thirat; and 5) Wat Phrom Niwat. In order to develop this royal temples there should be co-operation between locals and the private sector to promote sustainable tourism and to preserve the beautiful heritage sites as world heritage sites. The private sector and locals should support sustainable tourism activities and Thai culture to attract tourists who can encourage socio-economic development. In addition tourism facilities should be developed such as tourism landscapes parking areas tourism information public toilets and facilities for the elderly and disabled. Tourism policy should be supported through co-operation between locals and tourism stakeholders. Tourism management authorities and locals should support activities to preserve culture in order to attract more tourists and increase tourism revenue.

This research aimed to study Thai and foreign tourists about development guidelines of historical tourist attraction. 400 Thai and foreign tourists who came to travel at Ayutthaya Historical Park Ayutthaya province. A questionnaire was used as a research instrument. The statistics used for analyzing data were percentage mean and standard deviation. The results revealed that most the tourists were female ages 31 – 40 years old. Their education backgrounds were Bachelor’s degree. Their occupations were private companies. Their were Thai and Foreign. In general The Development Guidelines of Historical Tourist Attractions. The first of development guidelines were Attractive Factors (To what extent does each of the followings attract tourist?) and next were The capabilities to support tourism (To what extent does each of the followings support tourism?) and Management and Administration (To what extent does each of the followings affect tourism?). The top 5 of development guidelines were The remarkable and unique history Architectural and artistic beauty Greatness a good image and recognition Enough accommodations and Convenient access to tourist destinations