In an increasingly interconnected world, understanding the connectivity between marine and river ecosystems becomes essential for the conservation of our water resources and environmental sustainability. The i-MarCo International Congress 2026 is dedicated to exploring the complex interactions between rivers, seas, and oceans, and their impact on global biodiversity. This event brings together scientists, researchers, government authorities, and experts from various disciplines to exchange knowledge and foster constructive dialogue on best practices for preserving these vital ecosystems. Through presentations, panel discussions, and collaborative activities, the congress seeks to generate innovative and practical solutions to improve ecological connectivity, mitigate the effects of climate change, and promote integrated sustainable management policies.