Das ist beides

Hi, 
in 3.3 (Das Rathaus) and (Die Kirche) are referred to in the follwoing sentence as (Das ist beides im Zentrum).
Could you please clarify why a singular expression referred to two things? 
(i.e. why "Sie sind beide im Zentrum" is used instead?)

regards,
yahya.

I would agree "Sie sind" certainly seems more natural to English speakers.  Not sure I can answer it.  Das, as you probably know is can be more than just an article and can also represent pronouns such as this, that, it, and who.  Still seems like it should take a plural verb.  However, I found examples in Google translate where beides is used both with a singular or plural verb.  Example: Beides ist moglich.  Needs the umlaut, I know.

I guess we need a German expert to explain when a singular verb versus plural is used.  Collective pronouns are handled differently in other languages, I'm told.

German with Jenny to the rescue again.
https://www.youtube.com/watch?v=eb03gtUP0oc&t=133s
She explains how to use beide and beides, the catch is that beides is singular.