Well there are so many mosques in Tripoli...u can find more than 1 on the same street and people go to all of them because they are just a few steps away from their houses and where they work. Some are modern others are very old: One of the oldest is Taynal mosque buil about 700 years ago
Visit this page to see pics of some of these mosques:
http://www.tripoli-city.org/mosque.html