LONDON, England (CNN) -- The architecture of churches has undergone some major changes in the last century -- but has this been a change for the better or worse?
Is this ugly? The Third Church of Christ, Scientist's building in Washington D.C. is an example of brutalism.
Cathedrals and other church buildings have long been some of the world's most beautiful landmarks. But, since the 1950s a new type of church architecture has emerged and it is not being embraced by everyone -- including those within churches.
Consider these two examples from either side of the Atlantic.
In downtown Washington D.C. members of the Third Church of Christ, Scientist, were left unhappy when a historic preservation group had their 1971 building land-marked.
This move meant the church, which is an example of the 1950s and 1960s Brutalist architecture movement which promoted the use of rough concrete, cannot be altered or torn down. Church leaders, who had hoped to demolish the unsightly 60-foot structure were unable to do so.
Another ugly church in east Lancashire, in the north of England, attracted headlines after it was revealed nobody had married there for over 20 years as it was too unsightly.
The church, Rawtenstall Unitarian Church in the Rossendale Valley, was built in 1971 and has been described in London newspaper, The Times as an "ugly two-storey block house set between a betting shop and the town's four-lane ring road."
It may not come as a surprise that the church saw a long void in its marriage bookings after 1983. Church secretary, June Forshaw, told The Times: "I would not want the church in my wedding photographs. It is ugly. In fact, many families attending baptism take a five-minute walk to the nearby park to enjoy more pleasant surroundings."
These are just two examples of late 20th Century church architecture, but popular opinion appears to be increasingly negative towards many of these more functional or experimental structures which can deviate from how we expect a church to look.
One place where the dislike of such buildings is being discussed is the photo-sharing Web site, Flickr, where dozens of images of "ugly" churches are posted by interested observers and disgruntled residents from all over the world. Most of the images show churches constructed as very plain, low-cost buildings.
Of course, not all churches built in the late 20th Century lack beauty.
Richard Meier's Jubilee Church in Rome, the Crystal Cathedral in California and the works of Japanese architect Tadao Ando are examples of acclaimed churches to emerge from the period.
"Beauty is in the eye of the beholder," Antony Feltham-King of the Cathedral Architects' Association in Salisbury, England, told CNN, but went on to admit that some church designs from the latter half of the 20th Century are unpopular simply because they are outdated.
"The designs of the 1950s and 1960s are sometimes not considered attractive years on."
Feltham-King felt the move away from the classic church building towards buildings in prefabricated, mundane or windowless buildings was largely due to the prohibitive cost of repairs and maintenance.
"There is a huge financial burden of maintaining older buildings," he said.
As buildings age they become more expensive to repair and finding materials became more difficult, according to Feltham-King.
The worsening financial strain of maintaining old churches, along with declining congregations, is thought to be partly responsible for many churches being left redundant. An average of 30 churches per year fall into disuse in the United Kingdom alone.
But there is hope for modern church architecture.
Feltham-King said rather than constructing new, cheaper, and less attractive church buildings, some churches are now opting to upgrade their existing buildings using futuristic designs to complement the existing architecture.
The use of new materials could contribute towards reducing future maintenance costs, he said.
"The architecture profession as a whole has a desire to develop and evolve and that gets reflected in church architecture."
This innovative approach to ecclesiastical design marries new architecture with the old style in a cost-effective way, he said.
"The contrast says to the world that the church is moving forward and there are exciting things happening within it," Feltham-King told CNN.
The Church of England's director of cathedrals and church buildings, Janet Gough, said St Paul's Church and Community Center, in Bow, London, was a good example of how churches were being brought into the new millennium.
Gough said the new architecture was added with sustainability in mind, so creating something with the potential to produce income was important.
Matthew Lloyd Architects approached the challenge by creating a modern pod-like structure inside the 1878 Gothic-styled church, including modern additions like a gym, sauna and art gallery space for community use on site.
"It has a huge pod inside the main structure. All that [gym classes and sauna] goes on while the rest of the church can be used for traditional purposes," she explained.
The most important aspect of new developments like these is that they are "sympathetic" to the original design, so the two styles can work together.
So, if existing buildings can continue to be made more cost-effective, maybe the beauty of traditional ecclesiastical architecture can live on for a few generations yet.