As others have said Cathedrals (if you consider anything that has been build in the past 500 years modern) and I have seen Mosques that are breathtaking.
Religious communities have the motivation to build something that lasts and use the best of materials. They see the building as an act of worship, in and of itself. Cathedrals often took extremely long times to build. In some cases, such as the beautiful Sheikh Zayed Grand Mosque, they also have the money to build it both well and quickly.
Within many modern protestant Christian communities, building grand buildings is seen as a poor use of money that could be better spent helping people. These grand buildings are seen as less comfortable, efficient and flexible for modern congregations that would prefer lower cost, environmentally friendly and low energy building with community facilities.
Religious communities have the motivation to build something that lasts and use the best of materials. They see the building as an act of worship, in and of itself. Cathedrals often took extremely long times to build. In some cases, such as the beautiful Sheikh Zayed Grand Mosque, they also have the money to build it both well and quickly.
Within many modern protestant Christian communities, building grand buildings is seen as a poor use of money that could be better spent helping people. These grand buildings are seen as less comfortable, efficient and flexible for modern congregations that would prefer lower cost, environmentally friendly and low energy building with community facilities.