I visited the Niagara Falls two days ago in the company of a new business partner based in Toronto (and occasionally Bermuda). It was a pleasant mid-afternoon drive from Toronto in fine Autumn weather and the car was a better pace to discuss business than an office or the foyer of a hotel.

The Falls, when we reached them were spectacular, and mercifully quiet. I don’t mean the Falls themselves, which were thunderous, as you would expect, but the crowds. It was late Season and late afternoon and the selfie-stick wielding tourists were no great danger to life or limb.

It’s not a wilderness site anymore and it would be foolish to expect as much, but the brasher aspects of tourism are more or less kept at bay. Tall brand-name hotels and casinos tower over the gorge from a reasonable distance, and I suppose they must balance the need to provide their guests with a view with the need to preserve the atmosphere of the Falls themselves. I don’t doubt that most visitors would wish the hotels, indeed the whole town, were not there at all, but then there wouldn’t be jobs and taxes.

Worse than the hotels, casinos, souvenir shops and cafes, are the crumbling and brutal relics of early hydro-electric schemes which lurk just below the Falls. They’re as lovely in their dereliction as the abandoned industrial ruins of Eastern Europe which were built with equally complete disregard for the environment. But there’s still a rigorously defended strip of parkland that follows the gorge, and the Autumn leaves on Monday were splendid. With a little imagination you can picture the Falls as they must have been. And the water falls as reliably as it always has.

As great natural wonders of the world go, the Grand Canyon is better managed. Hotels are situated some miles away, and human interventions (pipes, walkways, toilets) are few. It’s a magnificent example of minimal intrusion and careful preservation. No cable car, no escalator, the only way up or down is on foot or on horseback.

At the other extreme lies Halong Bay, in Vietnam, which I visited in February. Magical from a distance, murky and polluted up close. A few quick bucks, no doubt made possible by corruption, are trumping conservation.

But pollution, sadly, is everywhere. Even three hundred metres below the Niagara Falls there is this foul mess…

But one mustn’t lament too much. Modern dentistry, at least, is some kind of consolation in the world we are spoiling.