Thirty years ago, in the summer of 1985, I slept overnight on a park bench in Florence, Italy. It remains one of the most memorable nights of my life.

I was not there by choice, but by chance. I'd arrived by train on my way from Milan to a place called Isole d'Elba, where I would be meeting two friends. I had come to Italy earlier in the summer at the behest of a modelling agency director who, as soon as I arrived, insinuated himself as a sort of parent figure. He was manipulative, however, and I eventually did what many young people would have done: I ran away.

At the time, I had very little money and no immediate means of getting more. On arriving in Florence, I learned that all the hotels were booked by school tours. I started to panic. My Italian was limited and my only friends in the country were back in Milan. There were no cell phones then, no email or Facebook, and I had no way of getting in touch with anyone to ask for help. Until I made it to Elba, I was alone.

I had no choice but to find a place to sleep. This was not easily done. As midnight approached and the crowds thinned in the streets, I began to realize how truly alone I was. With my limited Italian, I kept making inquiries about room cancellations at every budget hotel I passed (there was no chance of affording the expensive ones), but was almost literally shooed away by the anxious signore who feared I might disturb the school girls. (Little did they know I wasn't interested in girls!)

Eventually, I left the hotel zone and tried to find a quiet place to lay down where I would be undisturbed. That proved impossible. Wherever I went, I was noticed. At one point, a very insistent older man kept following me and asking how much it would cost to sleep with this "nice American boy." (No matter how much I tried, he didn't understand I wasn't American, but Canadian. In either case, I wasn't for sale.)

I eventually evaded him and made my way to a park on top of a mountain where I lay down, exhausted, on a marble bench. At first, it seemed a lark to be up there. I'd slept in tents in the wilderness plenty of times back home in Canada. But here I found myself in a very different situation, one where people could approach and disturb me while I slept.

I spent the night there, shivering (it was very cold.) An animal that looked like a wolf kept slinking around my bench sniffing for food. For a while, I worried it might be rabid, but eventually it left me alone.

I slept badly and woke just before dawn, cold and alone. I wrapped myself in a thin sweater and ate the only food I had: a chocolate bar, thankful at least for that small blessing. The next day I got back on the train and made my way to my friends who were waiting for me on Isole d'Elba.

I was lucky. I had friends and family who cared about me, and in fact nothing terrible occurred during the night. Still, it made me realize how vulnerable I was for that short period of time. The presence of predators, both human and non-human, made me understand just what it must be like for someone who has no choice but to spend time on the streets.

In two of my books to date, I have written about kids—abused, unwanted—who spent time on the streets. In a small way, I know what that feels like. It's something I wouldn't wish anyone to have to experience against their will.