Extended Abstract
Introduction
According to various natural, cultural and man-made attractions in rural areas, there is a variety of tourism patterns presented in different taxonomies based on different standards and criteria. Second home tourism and same day visiting are the common patterns in most rural areas in the country, particularly in mountainous areas surrounding the metropolitan regions. Tehran is a metropolis whose mountainous villages, due to their particular characteristics, are considered among the most important rural areas in the country. Because of having two tourism patterns as well as enjoying particular potentials, these areas have always been the target of researchers as the study area for their studies on tourism. To date, evaluating sustainability of the existing tourism patterns has been largely ignored in these studies since each pattern generates different effects. It is thus essential to evaluate the sustainability of rural tourism patterns and provide appropriate strategies for sustainable development.
Depending on different locations, the process of evaluating sustainability of rural tourism patterns requires thorough and comprehensive indicators and indices. Countless indicators and indices have been hitherto provided by organizations and experts in tourism. The significant issue is, therefore, localization, documentation, and operationalization of such indicators, since the set of indicators appropriate to a specified tourism area is not necessarily appropriate to another area. The question in the present study concerns according to sustainability indicators and indices in rural tourism, what are the indicators and indices for evaluating sustainability for evaluating the effects of tourism patterns in rural areas surrounding Tehran metropolis?

Methodology
The present study is fundamental in purpose and adopts a descriptive-analytic method. Documentation and questionnaire method have been used in order to formulate the indicators. The documentation method concerns reviewing the documents related to indicators of tourism sustainable development and analyzing their content. In order to formulate and operationalize the indicators and indices, the experts and public’s opinions were used in the questionnaire method. SPSS software (T test, mean, standard deviation, C.V, and factor analysis) has been also used in order to perform the required analyses.

Results and Discussion
After defining the dimensions, purposes, and stakeholders of tourism sustainable development and referencing to the literature, 117 primary indices were selected in the form of 15 major indicators. Based on 5 criteria of relation to the issue, access to the information, clarity and validity, measurability and comparability in different times and locations, the selected indicators and indices were evaluated by 35 experts using the Likert scale. Accordingly, the mean score of indices, based on the five criteria, indicates that all of the 117 indices scored above the mean (between 2.8 and 4.1). Further, the T test revealed that P value is less than 0.05. However, according to the experts’ viewpoint, some indicators could be combined or left out and by applying these changes a total of 88 indices were finally selected as the final indices. Finally, 5 villages in the periphery of Tehran metropolis were identified in which both of the aforesaid patterns were common. 30 questionnaires were then filled out by local residents and visitors. Accordingly, it was found out that the indicators and the characteristics of the study area were compatible.

Conclusion
By analyzing the content of countless foreign and domestic resources, albeit in the framework of tourism sustainable development approach, and according to the characteristics of rural areas in the periphery of Tehran metropolis, 117 indices were selected in this study. Using Delphi method, a total of 26 indices in the form of 4 major indicators in economic aspect, 41 indices in the form of 8 indicators in sociocultural aspect, and 21 indices in the form of 3 major indicators in environmental aspect of tourism sustainable development were formulated for evaluating sustainability of tourism patterns (second home and same day visiting) in the villages surrounding Tehran metropolis.