The Mer de Glace (literally, the "sea of ice") glacier can be seen up close and personal from the Train du Montenvers, a cogwheel mountain train that leaves from behind the SNCF train station. The hike back down is an easy two-hour ramble. From the top of the train you can mount yet another transportation device—a mini-téléphérique that suspends you over the glacier for five minutes.
Visit the Travel Talk forums for help on planning your trip