European Capital of Culture (ECoC), as a long-term cultural initiative of the European Union, has inevitably become intertwined with tourism development in designated cities. For almost four decades, medium-sized and small cities across Europe have been allowed to shift their local economies towards creativity and cultural tourism, driven by the ECoC title, with different cities achieving different levels of success. Since the 1990s, the ECoC initiative has followed the EU's trends, resolutions, and recommendations. The mid-2000s, 2010s, and early 2020s have given the trend a new drive with a more procedural approach in the ECoC bidding process. Sustainable development is one of the EU’s main strategic goals in the new era, and sustainable tourism has also influenced the ECoC initiative, making it one of the key priorities. This paper analyses the concepts of modern cultural tourism and the phenomena of over-tourism and sustainable tourism, especially in the ECoC context. Research methodology is based on secondary sources, including scientific papers, bid books and other official documents drawn up by ECoC cities and ECoC reports. The paper seeks to recognise and systematise the changes in cultural tourism trends in the ECoC context.