I traveled abroad for 2 weeks with only a carry-on and a personal item. Here's what worked — and what I wish I'd left behind.

When I set out on my first solo international trip — a two-week journey through Ireland, the UK, and Iceland, along with pit stops in New York and Chicago — I was plagued by one question: What should I pack?

Since I was only bringing a carry-on suitcase and a backpack, every item had to earn its place. By the time I got home, I made plenty of memories — and came to a much clearer sense of what I'd pack again, and what I'd leave behind.

Here are four items I was glad I brought, and three I could've gone without.

I'm glad I packed a light jacket that worked in so many different climates.

Even though I went on this trip in the summer, I knew several places I was visiting would be rainy. But because of the different climates I was going to, I quibbled over how warm I wanted a jacket to be.

I settled on an older, rain-resistant jacket that had lost some of its fluff rather than a light windbreaker. The jacket kept me warm in the Icelandic mist and didn't overwhelm me in New York during evening showers.

Right before my trip, I decided to get Icelandic krónur, British pounds, and some euros.

I spent a long time deciding whether to bite the bullet and get paper cash, wondering if that would even be useful. Since I was traveling alone, I erred on the side of caution and picked up some bills.

Even though I didn't use it every day — except at the airport and to buy some souvenirs at small shops — bringing local currency gave me peace of mind, and I would certainly pack it again.

If I had to pick one item as most essential, it would be my all-in-one travel adapter.

Since space in my bag was scarce, this all-in-one version was perfect, as it preserved room in my suitcase for other items and prevented me from bringing multiple adapters.

I always keep a pair of wired headphones in my bag with all my chargers. A few times on my flights, when a TV show wouldn't download in time, or my AirPods ran out of battery, my wired headphones were there for me to use for in-flight entertainment.