What cities have english language centers for young adults/adults?

I am moving to Colombia soon to teach.  Formerly, I was an English teacher in Bangkok, Thailand who taught mostly adults, university-age students, and corporate students in English institutes or learning centers.  I'm not too into the whole, young kids in a public school scene.

I've heard that Medellin has some of these.  Do you know which cities in Colombia have institutes or learning centers for late high school to adult-age students?

Here in Cartagena there is tons because it is a touristic city and there is a big demand to learn....one of the most well known is Colombo: colombocartagena.com/

There are English institutes in every city in Colombia.  Don't be too surprised when nobody speaks English at many of the institutes.  It's common.   Bogota pays better than the other cities from what  I have found and have many more opportunities available.   

good luck