I took a train trip across Portugal alone - and now I'm convinced it's the perfect place to travel solo

Portugal may be Europe's best-kept secret. It's more affordable than many of its neighbors, generally safe, and filled with friendly people. It's also easy to get to from the US, easy to get around, and completely charming.

I had so much fun on a solo long weekend in Lisbon a few years ago that I recently went back. This time, I took a solo cross-country train trip from Lagos, on Portugal's southern coast, through Lisbon and north to Porto.

I went back because I was looking for a place where I'd be comfortable traveling alone, where my family wouldn't be too worried about me, and where my dollars would stretch the furthest.

What I learned is that Portugal really is the best place on earth for solo travelers, especially those who have outgrown shared hostel rooms. But it's not just because of the affordable price tag - here's how Portugal won me over.