(CNN)Can a ring road be a thing of beauty?
Not if it's the concrete tunnels of the Paris Periphique, the semi-permanent parking lots that are London's Circulars or the dreary stretch of blacktop known as Washington's beltway.
In Vienna, though, it's a different story. OK, Vienna does have the Guertel, a boring loop around its outer suburbs.
But it also has the Ringstrasse -- born on May 1, exactly 150 years ago.
On that day in 1865, the country's Emperor Franz Joseph, gazed upon the only structure in the city more elegant than his enormous mustache and declared the "Ring" open for business.
Built in place of the city's old eight-meter-high defensive walls and moat, the street hugged the old town center for four kilometers in a grand semi-circle sprinkled with monumental buildings, green parks and majestic squares.
Nowadays the "Ring" makes for one of the most enjoyable city strolls in the world and a personal favorite.
My companion is Alexa Brauner, one of Vienna's top guides whose encyclopedic knowledge of the city is matched only by her juicy historical gossip.
We start at the western end by the round-fronted Urania Observatory (Uraniastrasse 1, Eingang Turmstiege, Vienna; +43 1 89 174 150 000) founded in 1910 as a Planetarium and adult education center.
It still operates as such and, along with the one in Berlin, claims to be the oldest in the world.
Hold on a minute, 1910?
"Not all buildings were completed at the same time," answers Brauner. "The Ringstrasse plan changed frequently and the last major building only opened in 1913."
And we're standing in front of it.
It's the War Ministry, finished, it seems, in time for World War I.
No such use for it in today's peaceful, neutral Austria: it houses a super-ministry that encompasses agriculture, social affairs and labor.
But it's Otto Wagner's Post Office Savings Bank (Postsparkasse, Georg-Coch-Platz 2, Vienna; +43 1 534 53-33088) opposite, finished in 1912 and still operating, that draws in the eye, with its hundreds of decorative iron bolts and aluminum caps -- 20% of the world's production of aluminum was used during its construction.
Magnet for photos
We're now past the Stubenring, the youngest part of the Ringstrasse but the oldest section of the walls.
Maybe the Viennese kept those to the end out of sheer sentimentality.
Outside these walls, a large wooded area was turned into Vienna's first public park, the Stadtpark.
In the middle lies the Johann Strauss monument, one of the city's most photographed monuments.
Strauss often performed in the nearby Kursalon (Johannesgasse 33, Vienna; +43 1 5125790) and it's comforting to know that you can still pop in there for a waltz concert every evening.
Brauner nudges me as we walk past the Palais Coburg (Coburgbastei, 4, Vienna; +43 1 518 180) sitting on top of a still intact section of the old city walls.
Once a palace, now a luxury hotel, it claims the largest Chateau Rothschild wine collection outside France.
Visitors can book a wine tour in its cellar, rated as one of the Top 10 in Europe.
We've reached the first major curve.
"The first sections of the Ringstrasse to be completed were here: the Kaerntner Ring, and the Opernring," Brauner says. "The boulevard itself is mostly built on the moat.
"Hotel Imperial on this side was built on the no-man's land beyond, while the Opera on the other side was built on the site of the battlements."
Hotel Imperial (Kaerntner Ring 16, Vienna, Austria; +43 1 501100) was the only building on the Ringstrasse built as a palace and belonged to the Duke of Wuerttemberg.
Its high-ceilinged lobby was once a carriage courtyard.
The location of the old stables can be found by walking further in.
Because of gambling debts, the Duke sold his palace quickly.
It re-opened as a luxury hotel in 1873 and state guests include Japan's Emperor Akihito, U.S. President Bill Clinton and Britain's Queen Elizabeth.
Now for the gossip.
Emperor Franz Josef led a double life, but was discreet enough to keep it secret.
His long-term concubine, Katharina Schratt, lived on the other side of Hotel Imperial, above what's now a physiotherapy shop.
Schratt's original apartments were destroyed by a U.S. Air Force raid on March 12, 1945.
The bombs also hit the State Opera (Wiener Staatsoper, Opernring 2, Vienna, +43 1 514 44) opposite, causing a fire that burned for 20 hours.
The Opera was the first major building inaugurated on the Ring, but some 1950s elements have crept in during its postwar restoration, not to everyone's liking.
"A Danish architect, Theophilus Hansen, was a major influence during the construction of the Ringstrasse," says Brauner.
"He raised money by convincing different investors to team together and pay for the same block.
"It would consist of four to six distinct houses with different entrances, but would be built as a single mansion, so every sponsor would appear to live in a house much bigger than his own."
We've now reached the Burgring and the Hofburg Imperial Palace (Hofburg, Michaelerkuppel, Vienna; +43 1-533 75 70) by Heldenplatz, the grandest square of the Ring.
Today, the Hofburg houses a string of minor museums, but one section facing Heldenplatz still has a similar use as before: it's the offices of the Austrian president.
The Renaissance-style Kunsthistorisches Museum (Maria-Theresien-Platz, Vienna; +43 1 52524), on the other side of the Hofburg, was built originally for the Imperial Art Collection and is still going strong as one the world's prime art museums.
The Natural History Museum (Burgring 7, Vienna;+43 1 521770) opposite is its twin and once considered its equal in importance. The 19th century was big on collecting plant specimens and stuffing animals.
Next to the museums stands Palais Epstein (Dr. Karl Renner Ring 3, Vienna; +43 1 401 10 0), a reminder that many Jewish bankers and industrialists invested in the Ring.
The terms were profitable: if they bought land, started building within the first year and they finished within four, they wouldn't have to pay tax on their earnings for 30 years.
Epstein sold quickly and the Palais has had a checkered history that includes serving as the Soviet Army headquarters after World War II.
Heldenplatz continues into the People's Garden (Volksgarten), that once stood within the Palace grounds.
Brauner stops by the 1950s modernist Volksgarten Pavillon, the perfect place from which to observe the Ring's mishmash of architectural styles.
Opposite us rises the Parliament, a neoclassical giant, completed in 1883.
It may have been mostly a talking shop for the peoples of the Empire, but it wasn't completely toothless: it eventually forced the country's Habsburg rulers to resign.
The Rathaus is next, still the Vienna City Hall (Friedrich-Schmidt-Platz 1, Vienna; +43 1 52550), with a neo-Gothic Cinderella exterior.
Catch it on a December evening with the Christmas market lights and you'd think you'd entered a Grimm Brothers' tale.
And then there's the Court Theater (Burgtheater, Universitaetsring 2, Vienna; +43 1 514444140) where we're heading, with its over-ornamented Renaissance facade.
Two side entrances lead directly to the Royal Box so that the Imperial family wouldn't mix with the common people.
Maybe it was for the better since those very people complained that the Ring had been built for show.
The tongues wagged: in the new Opera you couldn't hear, in the new Parliament you couldn't see and in the new Court Theater you could neither see nor hear.
It was seven years before the Burgtheater solved its acoustics problems, and even today the boxes still point more towards each other than the stage.
Brauner and I have reached the University Ring.
Side order of psychoanalysis
On the left towers the oldest German University, founded in 1365, and on our right lies the equally historic Cafe Landtmann (Universitaetsring 4, Vienna; +43 1 24100100), a classic Vienna coffeehouse.
Don't let the new glass front fool you -- this cafe can claim Sigmund Freud as a regular.
The last section of the Ringstrasse leads us to the Schottenring and the Stock Exchange (Auerspergstrasse 1, Vienna; +43 1 817 21 78), though with today's electronic trading, the stock brokers have long gone.
Many out-of-towners confused the building for the Imperial Palace itself -- with good reason.
It epitomizes the Ringstrasse era by saturating the austere lines of classical architecture with a bombastic over-decoration.
Yet opposite there is a reminder that this is 2015: Arabic lettering outside the baroque-looking building at number 21 Schottenring announces the Saudi-sponsored headquarters of the International Centre for Interreligious and Intercultural Dialogue (Schottenring 21, Vienna; + 43 1 313 22 0).
By now we're hungry so we walk into the basement of the Stock Exchange and to one of Vienna's many surprises.
We sit down at the chic Restaurant Hansen (Wipplingerstr. 34, Vienna; +43 1 532 0542) that looks onto a cavernous underground Garden Center.
What with all the tree saplings and flower fragrances, it's as if we've circled back on ourselves to the Stadtpark itself.
That's ring roads for you -- always taking you back, but some with more style than others.