Dark tourism is nothing new...

Remember the Roman gladiators? The arenas were full to bursting with spectators. In medieval times, the biggest attraction was a local hanging or execution.

In the mid-19th century, Thomas Cook organized tours of British travelers to American Civil War battlefields, and during the Crimean War a few years later, tourists led by Mark Twain visited the wrecked city of Sebastopol - he even scolded his travel mates for walking off with souvenir shrapnel.

And in Victorian England, tourists toured morgues. Since time immemorial, death and tragedy have fascinated people.

But where do you draw the line? Is visiting haunted castles and houses? How about Pearl Harbor? Or Inca ruins once used for human sacrifice?

Should you stay away from dark tourism?

It depends on the site, its history, and your relationship to it. It's a personal decision - so the more you know about it the better.

It also depends to a great extent on which end of the dark tourism spectrum you're talking about.

At one end are sites related to war and battle, like war memorials and cemeteries. I live in the foothills of the French Alps, where there are a number of memorials to Resistance fighters. I've been to many of them, as a homage to those who fought, out of interest, or simply not to forget what once happened. This type of tourism isn't usually considered controversial or wrong.

At the other end is the truly grim type of tourism, such as visiting a place where death is just taking place, like an execution, or where it has taken place so recently that any visit can only be considered gawking.

Visiting sites of questionable value can be a positive experience. It can help you gain a better understanding of history and of the world around you. Your visit and that of others may help contribute financially to an economically depressed area. And if you've been affected by the tragedy, however distantly, a visit can help you grieve and heal.

Conversely, there are reasons why you should not indulge in dark tourism. Your presence may be forcing people to relive a tragedy they'd rather forget. You can be perceived - and with reason - as disrespectful and insensitive if you've only come to gawk. You could be a voyeur, an exploiter. And, what you're doing may be plain morally wrong.