BARCELONA, Spain — Work on Barcelona’s breathtaking La Sagrada Familia Basilica, designed by visionary architect Antoni Gaudi, has entered its final phase of raising six immense towers that will make it Europe’s tallest religious building, surpassing Germany’s Ulm Minster. Presenting the project Thursday, chief architect Jordi Fauli said the central “Tower of Jesus Christ,” the tallest of the six, will make the architectural marvel that draws millions of visitors each year one for the record books when it is finished in a little over a decade. “The central tower of 172.5 meters (566 feet) will make it the tallest cathedral...