You might have a bit of a problem, the normal room with two seperate beds is not very common in Germany. What you normally get is a very large bed consisting of two mattresses and two duvets but contained in one frame. Twin bedded rooms do exist but not in a lot of hotels, you will usually get a twin bedded room in an American chain such as Holiday Inn but traditional German hotels don't always provide them. I would either ring the hotel or put a note on the booking that you want two seperate beds. Are you booking through an agency? if so there is usually a space on the form for additional requirements.

You should not assume that it can be sorted out at check-in and the small print of most sites will say that special requests in the notes box cannot be guaranteed.

As Judith says the most common option is two sets of mattresses and bedding in one frame (which doesn't really work as a twin or a double!).

I've checked the site I usually look at for Germany- http://www.hrs.de - and they don't offer the option to specify arrangements - just single, double or 4 bed family.

http://www.hotel.de does offer the 2 singles/1 double options if the selected hotel has them, but I have no experience of booking through the site although it does seem quite well laid out (and in English). It also has discount rates for advance reservations in some cases.

http://www.bestwestern.com also allows you to select if the options are available but has relatively few choices in Germany. Most offer advance booking discounts, which can be substantial (50% was my personal best!). Be aware that the dates fields on this site are in American format.

Make sure you are booking in the right Frankfurt, the big one on the Main (postcode beginning 6) or the other on the Oder (postcode beginning 1) near the Polish border.

Hey there thanks for your replies, managed to find a hotel and a good deal, sas raddison 4 star hotel for £142 for the room for 3 nights and its a twin room, thanks very much for your help.

Phew - glad you got sorted Jessop - don't forget your jimjams