"Regiunea cea mare este frumoasă."

Translation: The large region is beautiful.

[pereskia]

What is the purpose of cea here. Can it be omitted?

[Lng52-._]

Doesn't "cea mare" mean "the most beautiful"; e.g., "The region is the most beautiful"?

[Schattenparker]

(not native, but I guess)
cea mai mare = the biggest
cea mai frumoase = the most beautiful

but maybe
cea mare = so big, this big, uniquely big

So it is not a region that happens to be big among other things (regiunea mare și uscată) but the region known for being the big one like the "The Great Region" (regiunea cea mare).

A bit like Alexander the Great...?

Romanian natives, please correct me!

[abcdefg-1]

It'a bit of a strange sentence, but I think you are close with the region that is known for being big. I would translate "regiunea cea mare" literally as "the region that is big" or more naturally as simply "the big region."

[RuxandraBa20]

"The beautiful region is large" why is this wrong

[MarieOB9]

because the immediate descriptor of the region is "cea mare" which is big and the secondary is "este frumoasa" which is "is beautiful".
It's like the subtle difference between "the tall man is ugly" and "the ugly man is tall". You're using the first adjective as the identifier of the subject, and the second adjective is the purpose of the sentence

[8OhQ2fAw]

"That large region..." should be accepted shouldn't it?