Abstract
Due to its unique geographical position, Iran has simultaneous access to the Caspian Sea in the north and the Persian Gulf and the Sea of Oman in the south—an advantage that positions it as a key player in regional geopolitical and geoeconomic dynamics. In the meantime, the Caspian Sea—one of the world’s most significant enclosed seas—has gained renewed strategic importance in the post-Cold War era, particularly in the domains of energy, transit, security, and regional cooperation. This study aims to identify and analyze the geopolitical potentials of the Caspian Sea and its role in enhancing a regionalist approach to the development of Iran’s maritime-based economy. The research adopts a mixed-method (qualitative–quantitative), descriptive–analytical design. Qualitative data were collected through semi-structured interviews with experts in geopolitics, the blue economy, and regional studies, while quantitative data were obtained via specialized questionnaires and analyzed statistically in SPSS using Pearson’s correlation coefficient and the one-sample t-test. The findings indicate that Iran’s strategic position along the southern Caspian, coupled with its energy reserves, transit potentials, and environmental and cultural capacities, provides a solid foundation for fostering regional cooperation and advancing the country’s maritime economy. Moreover, the results confirmed a positive and significant relationship (p < 0/05) between the joint exploitation of Caspian resources and the promotion of regionalism in Iran’s blue economic development. Overall, the study concludes that by strategically leveraging its geopolitical position in the Caspian Sea and integrating its strategic resources with environmental and socio-cultural capital, Iran can establish a sustainable basis for developing a maritime-oriented economy. This approach not only strengthens Iran’s position within regional economic and political structures but also contributes to the formulation of sustainable national and regional strategies.

1. INTRODUCTION
Regionalism refers to the effort to create solidarity among at least three political units within a specific region and is considered a viable alternative to globalization. Iran, with its extensive coastlines to the north and south, has prioritized marine-oriented development, leveraging its maritime and coastal capacities as a strategic approach to economic development and land-use planning. Coasts play a crucial role in demographics, trade, energy production, and tourism. Iran's position along the Caspian Sea and the Persian Gulf provides a unique opportunity to take advantage of marine benefits. The discovery of oil and gas resources, combined with political changes following the collapse of the Soviet Union, has increasingly drawn the attention of both regional and extra-regional powers to this area. Alfred Thayer Mahan’s theory of sea power highlights the significance of geographical location, the quality and quantity of coastlines, and population as key factors for transforming a country into a maritime power. The Islamic Republic of Iran pursues policies of cooperation and equitable utilization of natural resources in the Caspian Sea, positioning itself as a central player in the economic sphere and in international collaborations in the region. Therefore, identifying Iran's geopolitical capacities and evaluating the economic impacts of regionalism policies on sustainable marine-oriented development are of paramount importance.

2. MATERIALS AND METHODS
The present study is descriptive-analytical research with an applied purpose. Data were collected from members of the Iranian Geopolitical Association (930 individuals) using designed questionnaires, and 271 participants were randomly selected. The questionnaires employed a 5-point Likert scale. Data analysis was performed using SPSS software, utilizing mean tests and Pearson correlation tests. Reliability was assessed using Cronbach's alpha coefficient, and validity was evaluated using the Lawshe method. To enhance the credibility of the results, eight experts in the field of geopolitics were selected for validation.

3. RESULTS
The Caspian Sea, recognized as the largest lake in the world, spans an area of 371,000 square kilometers and reaches a depth of 1,225 meters, effectively separating and connecting the Caucasus and Central Asia. This lake is bordered by five countries: Iran, Russia, Azerbaijan, Kazakhstan, and Turkmenistan, and has garnered international attention due to its rich oil and gas resources. Estimates indicate that the Caspian's oil reserves range from 19 to 200 billion barrels, while its gas reserves are between 299 and 991 billion cubic feet. Iran, with its advantageous geographical position and extensive coastlines, possesses a unique opportunity for marine-oriented economic development, access to natural resources, and the establishment of strategic transit routes to connect with global markets. These advantages could enhance trade volumes and energy supply for neighboring countries. The development of maritime transportation in Iran, particularly in the ports of Anzali and Nowshahr, could herald a positive transformation in maritime trade with Caspian Sea bordering nations. However, despite these benefits, challenges such as political and economic issues may negatively impact development. Conversely, opportunities for joint investments in energy projects and regional cooperation could foster mutual benefits. Additionally, cultural commonalities among the countries in the region could create a conducive environment for economic collaboration and cultural tourism. Iran's geographical position as a bridge between Central Asia and the Middle East plays a crucial role in the development of trade routes. By creating transit corridors, Iran could emerge as a key hub in marine commerce. Ultimately, despite challenges and sanctions, investment opportunities in infrastructure and the enhancement of cultural collaborations could significantly bolster Iran's marine-oriented economy.

4. DISCUSSION AND CONCLUSION
This research examines the geopolitical dimensions of regionalism in Iran with a focus on the marine-oriented economy of the Caspian Sea. The presence of oil and gas resources, along with global political changes, has heightened the significance of this region. The findings indicate that the geographical position of the Caspian Sea serves as a strategic point that influences regional geopolitics and could act as a catalyst for developing Iran's marine-oriented economy. The analysis encompasses four dimensions: 1) geographical location, 2) strategic resources, 3) environmental capabilities, and 4) cultural-social opportunities. The results highlight the positive impact of these factors on international cooperation and the enhancement of regional identity, providing a foundational basis for formulating Iran's developmental policies.