EVEN under the shadow of Notre Dame de Paris, surely one of the most magnificent of cathedrals, it was impossible to ignore the crunching underfoot of broken glass that the early-morning street cleaners hadn't yet removed.
Standing before the soaring shape of the Eiffel Tower, arguably the best-known landmark in the world, we couldn't help being distracted by the piles of rubbish scattered across the grass of the Champ de Mars.
Strolling along the beautiful embankment of the River Seine, walking hand-in-hand romantically, singing the old song Under the Bridges of Paris with You, we were almost overcome by the smell of stale urine.
Heading for the top floor of the magnificent Musee d'Orsay to see its extraordinary collection of impressionist paintings we had to clamber up eight flights of stairs ... yet there was an escalator to bring us down.
These are among the strange contradictions which continue to make Paris such a fascinating yet frustrating, romantic yet sleazy, welcoming yet surly, city to visit.
It was, of course, because of the city's romantic charm, welcoming cafes and restaurants and fascinating history, architecture and art that my wife and I chose Paris as the place to celebrate our 40th wedding anniversary.
But to insulate ourselves a little from the frustrations, sleaze and surliness, we splashed out on an excellent hotel, the Hotel Pont Royal, right in the middle of the delightful St Germain district, close to the River Seine and within easy walking distance of most of the city's attractions.
From the little balcony of our room, Paris looked serenely unchanged. To the right, on the top of Montmartre's hill, the elegant domes of the Basilica of the Sacred Heart of Paris - the Sacre Coeur - gleamed magnificently in the evening sun; to the left, on the banks of the Seine, the distinctive shape of the Eiffel Tower soared and across the road in front of a cluster of cafes, staff spread check tablecloths and distributed cutlery ready for dinner.
But when we ventured outside we found some things were a little different. For a start there was all the litter. I didn't think I was seeing Paris through a rose-tinted rear-vision mirror but I certainly didn't recall the city being quite so dirty previously.
The grass around the Eiffel Tower was almost covered in bottles, food wrappers and black crows fighting over food scraps.
On a more positive note, all the rude waiters and surly taxi drivers who made a lasting impression on previous visits seemed to have gone to charm school in the interim. Most were pleasant, helpful, tolerant of my awful French and able to speak excellent English.
This was such a shock that it almost came as a relief to stumble across one grumpy throwback, leaning on the wall outside a cafe, complete with thick moustache, black jacket and white apron, smoking a cigarette and contemptuously ignoring the arrival of any customers.
We were so charmed by this performance that we went inside, seated ourselves, found menus on another table, decided on a couple of salads and stubbornly refused to leave until he finally cracked and took our orders.
When he returned with our plates, he shouted something that sounded like "natking, natking" at my wife and I thought he was going to explode when she responded, "No, no, mine is the tuna salad."
Eventually it turned out he was asking her to remove her napkin from the space in front of her. "Gaaa," he snarled. "Can't speak French and now you're having problems with English."
The tuna salad was at least edible but my Nordic salad was so smothered in a ghastly dressing that I couldn't finish it. But I left him a tip anyway for providing such a wonderful journey down memory lane.
There was a bit of a contrast when we went for our special anniversary meal to L'Atelier de Joel Robuchon.
That's probably not surprising when you consider that Robuchon has been named as "chef of the century", the restaurant has two Michelin stars and we managed to get in thanks only to the good offices of our hotel's concierge (I have to admit I took considerable pleasure in watching the number of people who were turned away while we dined).
But not only was the food every bit as superb as we had hoped - my foie gras was the finest I've tasted and my wife still hasn't stopped talking about her pigeon supreme - but the staff were friendly, efficient and helpful. Whatever happened to hauteur - a word that might have been invented for waiters at fancy Parisian restaurants.
And you don't have to pay vast sums to have a pleasant eating experience, either.
On another day we stopped at a pleasantly down-at-heel bar for a reviving beer and enjoyed the atmosphere so much we ordered another, plus a chunk of the quiche de la maison which the amiable proprietor claimed he cooked himself - "to my grandmother's recipe" - and it was delicious.
There was another pleasant surprise when we took the Metro to Montmartre to see the Sacre Coeur. It was cheap, fast and reliable - and a uniformed official actually came out of her office to show us how to switch the ticketing machine to English.
Sacre bleu. Were we really in Paris?
Yes, we were, because only in Paris could you climb through narrow streets lined with old stone houses and see the beautiful white curves of the Sacre Coeur gleaming above.
And probably only in Paris would the approach to the church be transformed into such a colourful market, complete with immigrants selling cheap clothes, a gaily painted merry-go-round, a mournful accordion player and a lively old man producing marvellous music from his violin.
Gazing from the top of the basilica out at the skyline, which seemed to be exactly the same as when I first visited 40 years before, it occurred to me that one of the joys of coming back to a great city like this is that you can wander down memory lane without having to worry about getting lost somewhere horribly forgettable.
So, later in our stay, we were able to stroll along the banks of the Seine and enjoy the stalls selling books and magazines, awful paintings of Paris and reproductions of classic French posters, just as though it was still yesterday and we were still young.
On the Isle de La Cite the wonderful flower and bird market was once again in full swing. Notre Dame Cathedral, with its glorious stained-glass windows and superb carved screens, was as magnificent as ever and the little park behind the cathedral was still a haven of tranquillity in a sea of tourists.
These days, of course, the Louvre has that glass pyramid out front and the Mona Lisa's enigmatic smile is hidden behind a bulletproof screen - we'd decided to give it a miss this time anyway - but the fountains out front were still a fine spot to sit in the sun and watch the passing parade.
The Tuilerie Gardens were still perfect for a quiet wander and to enjoy the scattered sculptures, spread-eagled young lovers and small children sailing little boats on the pond in the middle.
For our fix of art this time we visited the wonderful Musee D'Orsay, savouring its magnificent collection of impressionists - Monet, Degas, Renoir, van Gogh, Cezanne - and in the process discovered that while waiters may have learned to cherish tourists, these great museums are still run primarily to suit the convenience of the staff, with considerably shorter opening hours than Te Papa.
We even found the Arc de Triomphe still managing to stand imperturbably at the head of the Champs Elysees despite the hordes of maniac drivers hurtling in every direction.
But there were still those contradictions. The French obviously take great pride in their past, so why were so many of the monuments we visited covered in litter or smelling of urine?
Paris has some of the world's finest art museums and fabulous places such as the Musee d'Orsay, to which the world flocks to see the works of the great masters, but why do they persist in opening such short hours and closing at least one day a week?
The city's once famously surly waiters and taxi drivers now give visitors a warm welcome - with the odd exception - so why is Charles de Gaulle Airport such an awful gateway?
And, most intriguing of all, how is it that during our few days in Paris we were three times approached by passersby, each of whom found a gold ring lying on the footpath at our feet and asked if it was ours? Well, I know the answer to that one. It's a con - the idea is you dishonestly keep the ring and give the finder a reward but later discover the ring is worthless - a con so old that I remember being warned about it decades before.
"Plus ca change, plus c'est la meme chose," as that great Parisian journalist Jean-Baptiste Alphones Karr once wrote. It could serve well as the city's motto.
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