The article provides an overview of the evolution of the idea of The Three Seas from its beginnings till the 2021 summit. According to the author, one of the impulses to its creation was the global confrontation that arose after the events of 2014 in Ukraine. This is felt notwithstanding the fact that this country is not yet a member of the project that celebrated its fifth anniversary in 2021. Today, this idea of uniting States in the space from the Baltic to the Black and Adriatic Seas, as well as when it originated, is actively supported by USA. In addition, the author shows how the attitude towards this program on the part of Germany and the European Union has changed significantly over the past six years. In fact, during this time, from Poland's attempt to realize its historical Central European ambitions, the initiative has transformed into a prototype of a new Central Europe, as an integral part of the Transatlantic community. In addition to the stages of development, the author examines the problem of the functionality of the new association, as well as its competitiveness with other regional entities, such as the Visegrad Group, the Central European Initiative, Slavkov Interaction, Chinese 17+1 initiative, etc. As a result, she comes to the conclusion that each of these structures, being an expression of the historical desire of the peoples of the region for rapprochement and finding a new role in Europe and the World, plays its own party and can compensate for the others, depending on the world situation.