Changes caused by the increase in tourist flow and change of guest structure who are looking for a holiday with more contents in untouched nature with the possibility of education, recreation and entertainment lead to a need to question the former model of tourism development on protected city surfaces. Zagreb has a preserved park heritage which constitutes an important part of the city’s tourist offer. The combination of natural beauty with cultural resources for the purpose of creating a new tourist product may encourage sustainable development and achieve sustainability. The work goal is to understand better the demand which will result in offer amelioration in a manner that will comply with special needs of Zagreb’s protected areas. This will also warn about the fact that the cultural and natural heritage situated in the very center of the City is not being used enough and about development of ambience tourism as an important part of the City’s tourist offer and identity. Four hypotheses have been formed in this paper. A field research has been performed via three questionnaires (for domestic visitors of Maksimir Park, for foreign visitors and for amateurs) in order to establish the existing activities, satisfaction with the offer and the willingness of foreign and domestic visitors to spend money while visiting Maksimir Park and to what extent do meteorological characteristics influence recreational activities. A quantitative data analysis with application of various statistical tests in MS Excel 2007 and IBM SPSS v21 (Statistical Package for Social Sciences) programs has been performed. The differences between domestic and foreign visitors have been analyzed by the Pearson’s Chi-square test. p<0,05 has been taken as statistically significant value. To confirm our first hypothesis: we suppose that the foreign visitors use more the facilities offered by Maksimir Park in comparison to domestic visitors, the Pearson’s Chi-square test being performed on 230 respondents (115 domestic and 115 foreign), in order to confirm the second hypothesis: we suppose that there is a statistically significant difference in perception of attractiveness of facilities offered by Maksimir Park between domestic and foreign visitors, the Pearson’s Chi-square test being performed on 230 respondents (115 domestic and 115 foreign), in order to confirm the third hypothesis: we suppose that the foreign visitors will be more proactive in selection of facilities in Maksimir Park compared to the domestic ones, the Pearson’s Chi-square test being performed on 230 respondents (115 domestic and 115 foreign). In order to confirm the fourth hypothesis (a study of amateurs in Maksimir Park has been performed) the following statistical tests have been used: analysis of variance (ANOVA), Pearson’s Chi-square test, t-test and discriminate analysis. The theoretical frame of the second chapter consists of five sub-chapters in which the scientific and professional standpoints on protected areas management in the World and in Europe have been analyzed and also the management concept and the institutional frame of protected areas in the Republic of Croatia and the City of Zagreb have been analyzed. In the third part the economical aspects of managing ambience areas of the City of Zagreb have been viewed, as well as the economic benefits of protected areas, financial funds that are being allocated for environmental protection, the goal of ambience tourism development and financial sustainability. In the fourth part, tourism as the factor of influence on sustainability is being viewed, through the systematizatio of the tourist resource base and visitation indicators. The characteristics of the tourist demand and evaluation of the tourist offer in Maksimir Park are being analyzed through the research results on needs, expectations and satisfaction of the Park’s foreign visitors and the evaluation of the visitors’ activity, offer valuation and demand characteristics are being analyzed through the research results on needs, expectations and satisfaction of domestic visitors. The goal of studying the domestic and the foreign visitors of Maksimir Park has been to determine whether the foreign visitors use more the facilities provided by Maksimir Park in comparison with the domestic visitors, to determine whether there is a difference in perception of the facilities’ attractiveness offered by Maksimir Park between domestic and foreign visitors and to determine the proactivity of foreign visitors and domestic visitors regarding the offered facilities in Maksimir Park in order to confirm or disprove the set hypotheses. The first hypothesis: the supposition that the foreign visitors use more the facilities provided by Maksimir Park in comparison with the domestic visitors has been viewed through the following parameters: there is a supposition that the foreign visitors, compared to the domestic visitors, are more satisfied with the offer of: renting bicycles, the gastronomic offer of Restaurant Maksimir, catering facility Vidikovac and Švicarska kuća, the cultural offer of the Gallery in the Haulik’s salon and the info-center services, educational activities and the offer of information materials and animated content for children. It has been concluded that the services that are being paid extra are much less used by the domestic visitors. In total, in a large majority the statistically significant differences in scoring the quality between the domestic and the foreign visitors are being shown and the Hypothesis one is being confirmed. The Second Hypothesis: the supposition that there is a statistically significant difference in the perception of the attractiveness of Maksimir Park facilities between the foreign and the domestic visitors has been viewed through the following parameters: there is a supposition that both the domestic and the foreign visitors consider the following to be attractive: renting bicycles, the gastronomic offer of the restaurant, catering facility Vidikovac and Švicarska kuća, the info-center services, educational activities and the offer of information materials and animated content as well as the offer of a boat ride on the Third lake. It has been concluded that there is a statistically significant connection between the domestic and the foreign visitors in evaluating the attractiveness of parameters. Domestic visitors have on many occasions evaluated the Natural heritage as attractive in comparison with the foreign visitors, and a statistically significant difference in opinion has been shown between the foreign and the domestic visitors regarding the subject of what the most attractive elements of tourist offer of this park are, by which the second hypothesis has been confirmed. The Third Hypothesis: the supposition that the foreign visitors in comparison with the domestic ones when selecting Maksimir Park facilities will be more proactive has been viewed through the following parameters: there is a supposition that the foreign visitors have been performing more the activities of walking, Nordic walking, have been using more the possibility of bird watching, boat ride services on the Third lake, that they have visited the Haulik’s salon Gallery more, ridden the bicycle more, used the services of bike rental more, bought more souvenirs and that they have visited the info center in greater numbers. The results have shown that the foreign visitors have used more the offer in comparison with the domestic visitors which has shown the statistically significant difference in proactivity between the foreign and the domestic visitors regarding using the offer and therefore the Third hypothesis has been confirmed. In the fifth part named ‘Comparison of sustainability of London and Zagreb’s park surfaces’ the sustainability of park surfaces of London and Zagreb is being compared. The touristic valuation of London’s Hyde Park is being viewed by the analysis of available reports. The sixth part named ‘Ecological aspects of ambience tourism sustainability’ consists of four parts: viewing of the environment utility, factors of tourist carrying capacity and their significance for ambience tourism, the analysis of transport access and connectedness as well as a research chapter where a research on connection between weather conditions and recreation in big park surfaces is being conducted. The Fourth Hypothesis: the supposition that there are differences in characteristics of amateurs in Maksimir Park considering the recreational activities in different weather conditions is being viewed through the following parameters: there is a supposition the there are differences in characteristics of amateurs between sunny days in all four seasons, there is a suppositions that there are differences in characteristics of amateurs in rainy days in spring and fall and there is a supposition that there are differences in characteristics of amateurs between a sunny and a rainy day in spring and fall. The results are a supplement to a better knowledge of the profile of amateurs and recreational activities in different weather conditions and they can serve as a starting point in a better quality concept of recreational offer of not just Maksimir Park and Zagreb’s green surfaces, but also of other cities as well. The final chapter named ‘Proposal of sustainable use of city parks in the function of developing Zagreb’s tourist offer’ views the sustainability of natural and anthropogenic resources, the main strengths and weaknesses have been ranked by their significance and identified by a SWOT analysis of internal resources, and circumstances and threats according to the probability of their occurrence are being identified. By comparing Zagreb to more developed European surrounding, it has been established that Zagreb has a high diversity and highly preserved natural values, and it has been concluded that the valuation and protection of natural resources have been one of the main strategics in development, especially in tourism, which is being shown in more detail in the strategic vision of development and the marketing development strategy. Based on the research results, the following conclusions have been made: distinguishing symbols of the City make up attractive factors, even though they lag behind the needs of a modern visitor, an amateur or a tourist. The society’s development can be seen in the way the parks have been decorated, managed and in their offer. Parks, besides being ecologically and recreationally important to the inhabitants, make up the economically unused potentials that may provide sustainable, long-term economical activities by providing health and economical benefits for the local community.