sagrada familia
A Catholic basilica in Barcelona that is, as of 2023, the largest uncompleted one in the world. Designed by the Catalan architect Antoni Gaudí, ground was broken for it in 1882, but due to various circumstances including construction stopping and starting, it is currently scheduled to be completed after 2026. However, UNESCO has designated it as a World Heritage Site and Pope Benedict XVI both consecrated it and named it a minor basilica.