WASHINGTON, Oct. 29 (UPI) -- It's not every day that one can execute the unrealized vision of Leonardo da Vinci, but a Norwegian artist has done just that.
Half a millennium has elapsed since Turkish Sultan Bajazet II commissioned the Italian Renaissance master to design a bridge to span the Golden Horn, an estuary in Istanbul's harbor linking the city to the town of Pera (modern Beyoglu). Leonardo drew up plans for an elegant 720-foot "pressed-bow" stone structure that was 300 years ahead of its time.
Pressed-bow construction allows relatively slim, graceful arches to support great loads through the use of wide footings. But technology at the beginning of the 16th century could not guarantee the success of such an ambitious project. The sultan balked, and the bridge was never built.
All that remained was a small drawing and Leonardo's letter to Bajazet II.
In 1996, Vebjørn Sand, a Norwegian painter also known for his public projects, was smitten by a model of the bridge at a Stockholm exhibition devoted to da Vinci's engineering genius.
"The design is beautiful and eternal because of its conformity with the laws of mathematics and geometry," Sand told United Press International.
He immediately took the idea of building the bridge to Norway's Transportation Ministry, but a workable plan emerged only after years of collaborating with various architects and engineers. A sleek timber version of the original design will open Wednesday. The scaled-down, 328-foot structure spans the E-18 Highway, linking Oslo, Norway, with the township of Ås, Sweden for pedestrians and bicyclists.
Three arches of laminated cedar support the walkway, "two side bows and a center bow." The Moelven Group of structural engineers developed the special gluing process, which it used to build the Viking ship ice rink at the 1994 Lillehammer Winter Olympics.
"Norway has a tradition of picking up impulses from the continent and transform them into what we have built our country with -- and that's wood," Sand told UPI. He said Oslo's new airport, which encloses Norway's largest interior space, also is built with laminated wood.
Leonardo found the midpoint between aesthetics and the laws of physics, between the spiritual and material realms, between cultures, and between heaven and earth," Sand said.
"It was amazingly futuristic. It didn't look like a 500-year-old design," the artist said. "When you work with geniuses, you work with eternal forms that never go out of fashion. Architecture from the 1970s looks older than Leonardo's design."
Sand said its spiritual power gave him energy and momentum in his effort to have the bridge built.
When he got back to Norway and saw the ugly gray concrete bridges that spanned the highways, he contacted the Norwegian Transportation Ministry and showed them the design and pictures of the model. "We can really make history," he told the ministry.
The "Norwegian Leonardo Project" consists of the wooden pedestrian walkway and a stone bridge to be built at a location as yet to be determined. Iowa is strong contender, Sand said.
Asked about the foundation for the Norse bridge, Sand said the builders dug until they hit rock. Concrete piles were constructed upon the rock, and the wooden footings were mounted into concrete. The laminated cedar bows are reinforced with steel only at their bases.
A new, non-toxic wood preservative from Jotun Paints of Norway replaces creosote, the ugly, tar-like substance used on telephone poles. "No poisons," Sand said. "This is a green project."
The artist, who hopes to build a Leonardo bridge on every continent, is primarily a figurative painter in the tradition of the old masters. This makes him something of a maverick in Norway, where the modernist style has reigned supreme for decades.