07. Cathedral of St. John the Divine
It is one of the largest churches in the world but can you imagine that it is also incomplete. It was proposed in 1921 that it will take 700 years to complete the building due to the true Gothic building methods. The ground was broken for the nave in 1916. This cathedral is located on Amsterdam Avenue in New York City. It is currently over a century old and the construction will be continued over the coming decades. Still there is no final timetable about its completion but it is one of its own kinds of structure.