takes XXX km's trip? with XXX population?

Is the following sentence grammatical?

It takes 16 km and 25 km’s trip to go to Bransdon (with 15,000 population) and Cransdon (with 29,000 population) respectively.

I have two doubts:

• Can one really say "it takes 16 km and 25 km's trip to go to ..."?

  First, I think one can only say "it takes xxx hours to go to xxx" (takes time, not distance)​ Second, suppose one can say "it takes xxx km", is it correct to say "it takes a 16 km's trip"?​

• Can one really say "with xxx population"?

  I think one can only say "with a population of xxx". Is this correct?​

However, you can say it's a 16 km. trip to Bransdon (pop. 15,000). It might be clearer to go on … and a 25 km. trip to Cransdon... rather than quoting both figures together and using respectively.