This saturday I will be leaving for Germany for a conference in Munster. I'll go by train on my way there I'll stop by at Freiburg for a couple of hours and on my way back I'll visit Cologne. I was wondering if any EFers have any specific recommendations for these 3 places, a must eat or a must see?

Depends what you're interested in.

Freiburg:

The old town is definietly a must see. Lots of really scenic spots, especially in the upper part of the town (Oberlinden area). I recommend exploring some of the side streets there.

The streets of the old town are famous for their "Bächle", little streams running along the streets which cool the town in the summer. Locals claim that you cannot claim to be a Freiburger if you have never fallen into one. Freiburg's streets are equally famous for their mosaics which usually reflect the trade of the adjoining shop in some way, or otherwise somehow connect to local history.

Freiburg also has two old town gates that date back to the 13th Century. The Schwabentor is one of these and the paintings on it tell the amsuing yet cautionary tale of a Swabain farmer who got rich quickly and decided to buy the town of Freiburg. He arrived in the town with what he believed was a cartload of gold. When he opened the sacks however to prove his intentions to the sceptical city fathers, the sacks turned out to contain only sand. He was ridiculed and chased out of town. His wife, who opposed his idea had secretly changed the sacks.

If you have time, go inside the Münster or climb the tower (if you're not afraid of heights and are sure of foot, the stairs are quite narrow and scary in places).

Freiburg also has lots of street cafe type places so just sit back and relax. The best place for these is on Münsterplatz or also around the university.

Cologne:

The most obvious tourist attraction in Cologne is its world famous Dom (cathedral) which is on the UNESCO world heritage list. This is just across the street from the station so easy to do while you're passing through.

In Cologne.

If you go into the Cathedral, make sure you see the ruins underneath the existing one.

For real, authentic Cologne, there are a couple of great pubs with good traditional food.
Everything is within walking distance of the Cathedral and Main Train Station.

Brauhaus Malzmühle (evenings best)
http://www.muehlenkoelsch.de/de/home.php
Wooden floors, walls, tables and chairs. Gemütlich halt.

Cölner Hofbräu Früh (Frühshoppen - Sunday morning breakfast - egg and bacon too! - with a glas of Kölsch - TRADITION)
http://www.frueh.de/
The architecture inside is not to be missed and the beer garden in front is great too.

For eating out, try the XII Apostel.
http://www.xii-apostel.com/12-apostel-koeln/koeln.html
Simply wonderful.

I've stayed in the Dom Hotel on business trips before. Not the best, but clean business hotel, good value for money (especially if you have to pay yourself), great breakfast and so central. In 3 minutes you can walk down to the old town and it's 2 minutes to the main train station.

Papa Joes Jazz Bar is a nice venue tight on the River for live music. Walking distance from the Chocolate Museum (great If your wife is with you) which is open Sundays too I believe.

Kölle Alaaf! (as the Rheinländer say)...

in cologne, if you go down to look at the dom ruins, be sure to head up and climb the tower. If it is a nice clear day, you get a great view!

the museum ludwig is fantastic.

and for food, i loved the variety of ethnic foods! Yes, Fruh in the old town is a great traditional german place, but I had amazing and super reasonable Tapas, Japanese, Mexican, etc.

One place, and I can't remember the name is a to-die-for Lebanese restaurant in the old town, about one block up on a street parallel to the river. It is popular so you may be able to find out the name by asking at your hotel. It was the best meal I had when I was there!

Have a great trip!

thanks a lot for the ideas! I have only 6 hours in cologne but i'll try to see as much as I can