Translation of mainstream in German

The place was really modern and the food was excellent. We later found out that the restaurant belonged to a chain with the same name and was present all over the country and pretty popular.
The cafe was not cheap but the food was quite special. In the back there was a travel agency, again not the cheapest one but they made a very reliable impression and that is why we booked with them.
If you want we can exchange messages and emails in English and Spanish in order to improve and get some exercise. I think we should correct each other's messages. i need to practice otherwise I will forget everything.