Bali is a great and accepting place to travel solo, with amazing beaches and underwater exploration sites, it makes for a perfect place to snorkel and scuba dive and explore the many temple sites.
If you are Eco friendly then you would definitely love Costa Rica as you can explore and learn more about sustainability. You can enjoy watching some nesting of sea turtles and enjoy the surf at Playa Bonita.
Wales has amazing landscapes and great cultural history and focus on mythology. You can enjoy the outdoors and go on a solo hike on the Pembrokeshire coast or visit Cardiff, the capitol and enjoy the museums and shopping centers.
Canada makes for a great solo journey as it feels extremely safe. In Quebec, you’ll find a huge cinematic and television culture. In Toronto you can explore the theater and music scene and comedy venues. You can also check out the national parks, from Niagara Falls to Mount Revelstoke.
The culture here means bars and restaurants are familiar with solo travelers. It’s great for foodies and backpackers.
Norway, Finland, Denmark and Sweden have some of the lowest crime rates which makes it great for solo travel. Visit the Fjords in Norway, hike and camp in Sweden or walk the cobble stones streets of Denmark.