The fifth arrondissement is the latin quarter and perfect for lively Paris breaks with a youthful feel, cosmopolitain cuisine and swinging nightlife.
This is the famous Left Bank, which to Londoners looking at the Paris city map looks more like the southbank but never mind that. This is teh country which has 15 days in a fortnight afterall.
So what os there to see in the 5th, well there's the Pantheon - a big temple like structure on the top of a hill with a large dome, there's the zoo and gardens and Jardin des Plantes, and the Museum of the Arab World.
The area still has a significant student presence, with several universities and schools of higher education being located in the 5th arrondissement but a lot of students and faculty have been forced to more affordable areas such as the 13th arroondissement.
So it's a tourist area now, with affordable hotels and restaurants for visitors and plenty to see and do.