Hi,
banh.de has a special for families called Happy Weekend tickets according the website:
http://www.bahn.de/international/vie...many/swt.shtml

As I dont understand German I couldnt find any more info. We will be arriving at Frankfurt Airport on a Saturday. Can me, my husband and son use this to travel to Cologne. Do we have to buy this in advance?

Thanks for your help - I dont know what I will do without this forum!

Of course you can use it. It is valid for up to 5 people travelling together, in case of families for parents and all their children under 15, no matter how many.
There is only one vital information missing on the page you linked: This ticket is valid on local trains only, no ICE and IC/EC. This means the journey will take longer and require changes (probably at Mainz and Koblenz in your case).

When looking up train connections on http://www.bahn.de, tick "only local trains".

There is no need to buy the ticket in advance, you can get it from a ticket machine or counter at the station.

jandee- Deutsche Bahn has several very good deals for groups. The great thing about the happy weekend ticket is that it isn't limited geographically. But you might have also noticed on the website that they have "lander tickets" also - these you can use for a single day during the week (or weekend, I think) for travel within any one state. They are also good for groups up to five. One thing I also found out about during a trip to the Frankfurt area last fall is another kind of ticket called a mini-gruppe (mini-group). I never noticed them on the website but you can buy them at the ticket machines at any train station. When you buy these tickets you specify two points along a line - Koblenz and Cologne might be one example - and your group may travel anywhere between those two points as much as you wish for an entire day. And they are often even cheapter than the lander tickets.

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Great info! Thanks

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