This is a true beauty and a great excuse to go back to Paris real soon. In the Bibliothèque nationale de France you can find this exhibition (until January 27th 2013): L’Âge d’or des cartes marines – Quand l’Europe découvrait le monde (The Golden Age of Sea Charts).
Not alone are the maps in the exhibition beautiful and gives the expo a great overview of the discovery of the world and this category of maps, the library did a great job on presenting the subject. The website looks stunning. There should be a free iPhone and iPad app for the exhibition any day now, the catalogue looks very promising and the design of the exhibition (by Véronique Dollfus et Jeanne Bovier-Lapierre) should give you the immediate feeling you step into a portolan chart. Plus: 350 maps are made available on Gallica (the digital ‘jewel box’ of the library). This expo is a must go if you ask me. And let me know if you’ve visited the BnF!