It would help to know your starting location, but I’ll assume it’s the US or Canada because you didn’t say. My first thought for this is Argentina, which of course is in mid spring in late October. Buenos Aires is a wonderful city with great food and culture. You could also visit Mendoza, which is the lovely wine region, and Bariloche, which is a mountain resort area with year-round activities and such. Then there is always the amazing Iguazu Falls on the border with Brazil and Paraguay. It’s by far the most amazing waterfalls and area I’ve seen. Things are pretty cheap in Argentina these days for outsiders because of their weak currency. It’s also got very good outdoor activities in many different areas that should have nice weather in late October. It’s easier if you know Spanish, but still doable if you don’t. I don’t speak Spanish and I enjoyed it so much I stayed for a month. Let me know if you have something else in mind and I can try again. -Roger

If you are open to Africa you should consider Morocco. It will be a bit chilly in December, but still warm enough to enjoy everything. The culture there is fascinating and it’s also very tourist-friendly and safe. I think it would be cheaper for you to fly to Morocco than to the Americas, and the daily costs are very reasonable as well. Those should give you some things to think about, and feel free to follow up if you have other questions.
Your Munich plan sounds good. It can be fun to actually spend a full night in a town like Rothenburg ob der Tauber because it’s filled with day-trippers in the day and you almost have it to yourself at night. But it’s small enough that one night there would be enough. Nuremburg is quite a large city, and you might even stay there a night or two as well. I don’t know if I’ve ever heard of anyone saying they enjoy the cold and the rain, but if you do you’ll love it there. Fortunately, nowhere in the popular parts of Europe do they get extreme winters, and there is a good chance you won’t even see any snow in those cities. Most people are looking for the warmest places, which can be found in Portugal and Spain, but since that isn’t you I think your plan is good. Christmas is a big deal in some European cities such as Rome, but not a huge deal in others. Most businesses will be closed that day in nearly all countries, but of course hotels and many restaurants will be open. I hope this helps. Let me know if you have any other questions. -Roger
Costa Rica, as you probably know, is all about nature and adventure sports, along with some decent beaches. It would be perfect if you are up for that sort of thing. If not, Santiago and Valparaiso (nearby cities in Chile) could be good for more of an urban adventure. Or Buenos Aires is even nicer and more interesting (and probably cheaper if you bring cash) if you can get a deal on a flight there.

If you’re a bit more on the timid side, you can always use Yelp and TripAdvisor to get good insights on places people have visited. As a disclaimer, some of the ratings may not be accurate on these sites, so make sure you go through and read some of the more recent reviews that people have written. We did this for a few of the places we visited and had no issues.

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