Someone who knows your plan, cover that actually pays out, and a clear head about what to do if something goes wrong — so you can stop thinking about it.
Not because solo travel is dangerous — enormous numbers of people do it safely every year — but because nobody has a plan for the unlikely thing.
The address, the emergency number, the policy, the one person you'd call. All of it, in the one object most likely to go missing.
Medical care abroad and a medical flight home are the costs that turn a bad trip into years of debt — and they can't be arranged retrospectively.
'Don't walk alone at night' is true everywhere and useful nowhere. Which scams run here, how do they open, and where do you check what's actually current?