When followers of the newly formed Bahá’í faith chose Chicago’s tranquil North Shore as the site for their North American House of Worship in the early 1900s, they dreamed of a building that would embody a sense of unity—one of the central tenets of the religion’s belief system. Architect Louis Bourgeois’ ambitious design did just that, and more than 60 years after the soaring structure was completed, it’s still bringing people together with its diverse influences, unexpected architectural style, and commitment to preserving that original vision.

Completed in 1953, the striking House of Worship draws thousands of visitors each year. And for good reason. The towering, ornate white dome doesn’t exactly blend in with its suburban Illinois surroundings. But according to Scott Conrad, manager of the National Bahá’í Properties Office, the intricate building and its grounds actually make a lot of sense if you consider their setting.

“I feel that it speaks strongly to the Chicago tradition of architecture. The ornamentation when one studies it has a very Louis Sullivan or Sullivanesque quality to it, which is not an accident because Bourgeois at one point in his career was associated with and worked with Louis Sullivan,” Conrad says. “This is only an opinion, but the Bahá’í temple kind of reflects the White City, the 1893 [Chicago] World’s Fair.”

And like the exhibitions constructed for that event, the House of Worship also celebrates a worldly and innovative disposition. The faith, founded in 1863 in what is now Iran and introduced to America at the turn of the 20th century, teaches that all the world’s major religions are different paths to serve the same God, so the temple was designed to reflect that.

“What the architect was trying to do was to incorporate in a cohesive way were different religions’ iconic styles of architectures into one building and I think it’s successful,” Conrad says.

Bringing that bold concept to life in the early 20th century, however, required some ingenuity—not to mention decades of work. In order to achieve the intricate details on the dome he imagined, Bourgeois consulted with ornamental concrete expert John Earley and massive cast concrete panels were created using white Portland cement and crushed quartz, a practice that was almost unheard of at the time. And because such an unusual building method was used, preserving the property has presented its own challenges over the years as well.

“It’s really a gigantic sculpture outside in these incredible gardens. And that makes it very unique,” Bob Armbruster, who helped lead several restoration projects on the property in the 1980s through early 2000s, says. “No one had been producing concrete of this type, something so sculptural. So we basically had to reinvent the process and I had to locate sculptors who could actually restore the shapes and craftsmen who knew how to produce molds good enough for concrete and all the different issues.”

In addition to regular maintenance, work was completed on a cornice on the base of the dome in the early 1990s, monumental stairs received needed repairs in recent decades, and the temple’s elaborate gardens were restored to their original, never-completed design in 2012. Other projects, Conrad says, are on the horizon as well: “A building that large and complex is always requiring ongoing work.”

Conrad’s and others’ dedication to the property have kept it a sacred destination for both followers of the Bahá’í faith and curious visitors from around the world. So many visitors come to admire the space, in fact, a new visitors center was built and opened on the grounds last May.

Echoing a landscape architect who worked on the plans in the 1940s, Conrad recommends visitors experience the House of Worship on a summer evening.

“Louis Bourgeois called it the temple of light, and I think the idea of the Bahá’í temple design as I understand it was that light from the outside could come in through all the perforations in the precast concrete and at night all the light could come out through all this ornamentation. So it has almost this exquisite oriental lantern type quality to it,” Conrad says. “So being at the lakefront where the northern branch of the Chicago river starts, you have this kind of beautiful domed building that has this kind of oriental quality to it, surrounded by gardens. It’s a spectacular setting.”