Overtourism has been a buzzword in the travel industry for some time now. Reports of overcrowding at major tourist sites and in national parks have raised concerns about the future of our natural wonders and attractions across the world. And unfortunately, it's still a rising problem. This year, a whole host of destinations simply became too crowded, resulting in closures and tourist bans in destinations such as Amsterdam and Iceland. These are the places that were worst affected in 2019.