"The journey is very popular among tourists."
Translation:Rejsen er meget populær blandt turister.
They mean the same, but 'iblandt' can be used both as a preposition and as an adverb, while 'blandt' only can be used as a preposition.
So in the sentence above you can use both, but in this sentence you can use only iblandt:
'Der var mange populære rejser iblandt' = there were many popular jouneys among (them)
The same goes for some other prepositions in Danish: imod/mod =against; igennem/gennem = through; imellem/mellem = between etc.
Actually, as I come to think about it is the same situation with between/in-between in English
That should definitely be "blandt". I can't give you the exact explanation but I feel like "iblandt" is only used for A actually being among B, so you could say, for example, "der er mange kinesere iblandt turisterne" or "iblandt de unge var der også et par gamle". But this is a case of A (a travel, an abstract thing) being popular among B (tourists, a concrete thing). That doesn't work with iblandt.
Tur may be used about any movement from point A to point B, say, a trip to the drugstore or the park or even to the toilet. Rejse is a journey of some length and duration, including multiple forms of transportation, such as a trip to Rome or to the moon or to the other end of the country. You can also use tur for those though, if you want to make it sound a little less formal and daunting and exciting.
This started me thinking about the difference, and in the English equivalents, i.e. tour and journey, tour would be used if you are viewing things along the way, and journey if you are travelling between two points (to then maybe see something when you arrive at your destination. Don't know if that helps : )
It sounds like better equivalents would be 'trip' and 'journey' rather than 'tour' which does sound like 'tur' but I think the idea of informally going to somewhere is best called a trip in English. Eg a trip to the supermarket or the park. If I've correctly understood the meanings
I definitely agree those are better equivalents. For the word "tour", we have rarer words like "rundtur" or "rundrejse" which imply that you go to several points within the same larger area. If it's a smaller area (such as the living room), you'd go for "rundvisning". For most uses of "tur", "trip" will be fine. However, you can think of "tur" as even more widely used than "trip". If I announce that I'm going to go for a walk, you may afterwards ask me: "Har du haft en god tur?" It's also common (although superfluous) to say stuff like "Jeg skal lige en tur ned på apoteket" or even "Jeg skal lige en tur ud på toilettet". It makes those sentences even more casual.