La Grande Mosqueé de Paris is one of my favorite places in Paris. Being the biggest of its kind in Europe, the mosque has both a cosy little cafe where you can enjoy a 'thé à la menthe', a beautiful praying room and a stunning courtyard. The silence here is amazing and hard to find elsewhere in the City of Lights!
The mosque is open everyday except Friday from 9am to 12pm and again from 2pm to 6pm. The entrance is 2€ and even though visitors are welcome, always remember to be respectful of the environment.