In Colossians 4:16, Paul asks that the letter also be read in the church of which city?

Answer: Laodicea

After the letter was read in Colossae, Paul wanted it read in the church of the Laodiceans, and the Colossians to read the letter from Laodicea.

“After this letter has been read among you, make sure that it is also read in the church of the Laodiceans, and that you in turn read the letter from Laodicea.”— Colossians 4:16 (BSB)