Line break using Concatenate

Hi,
I was wondering if there was a way to use the function Concatenate and insert a line break.

I.E.
Cell A1 has the data 1234
Cell B1 has the data 5678

I want cell C1 to display the data using concatenate as:

1234
5678

However, in using concatenate I can't figure out how to insert a line break between the data in A1 and B1.

When i use the formula Concatenate(A1,B1) I get:
12345678 in C1 when my target is

1234
5678

Thank you it works.

Also, I found out that I could do:

Concatenate(A1,[alt+enter]A2)
then wrap text and it works the same.

Thanks again