Helsinki Cathedral, also known as St. Nicholas's Church, is a famous landmark in the heart of Helsinki, Finland. Built between 1830 and 1852, this neoclassical beauty with its green dome and four smaller domes stands tall at Senate Square. Designed by Carl Ludvig Engel, it's a popular tourist spot and a hub for worship services and special events like weddings. With its rich history and stunning architecture, the cathedral is a must-visit attraction in Helsinki.