"The bathroom is next to the restaurant."
厕所 Cè Suǒ not OK? When I was in China it was never called anything else!
卫生间 Wèi Shēng Jiān not accepted either!
Why not 饭馆的旁边是洗手间 ？ An earlier question in the same session used that format to describe something located next to something else.
As Diego implies in his response, your construction reverses the subject and object of the sentence.
Instead of 'The bathroom is next to the restaurant.' your construction is more like 'Beside the restaurant there is a washroom.' Your Chinese isn't wrong, but it reverses the sense of the English.
I guess because of the sentence construction. Yours would more likely be translated like: Next to the restaurant is the bathroom. Even thought it would mean the same, Duolingo seems to be strict on translations
洗手间在饭馆旁边 worked fine for me. They must have added it! On a separate note, are restaurant bathrooms in China outside the "main" establishment? Of course, I am not referring to modern buildings. The expression reminds me of old gas stations in US where the bathroom(s) have separate doors from the main gas station store...
In older districts there are often public toilet buildings, usually of two storeys (some apartments in these areas may lack their own toilets). Nice restaurants always have washrooms, but small cafés/restaurants in these districts mightn't and could conceivably be next to a public facility. That's what I imagine this sentence suggests (or else the truck-stop possibility.)
You need a 的 between 饭馆 and 旁边. Usually, a 的 is needed to refer to possession (there are some exceptions regarding close human relationships).
it's for the sake of learning the proper gramar and to show to the particle 的 links these two
Thanks for explaining the function of 的. From the tips, it sounds like the use is arbitrary.
饭馆的旁边有洗手间 this was how I learned it in my Chinese classes. So, why is it marked as incorrect?