BAG SIZE

[jason]

As a potential first time backpacker, I am interested in how big of a bag I should get if I plan on travelling for about a month this summer in europe?
By the way, I will have two to three other friends coming with me so maybe we could divide up some of the essential things we need.
P.S. can you answer with dimensions and volume, any help will be greatly appreciated

[Eagle]

As a general rule it's always a good idea to pack light. I'm going to be using an Eagle Creek Continental Journey pack on my travels -- it's about 3900 cu. in / 64 L. total, with the detachable Daypack. It's supposedly "carry-on size" (without the Daypack) but it sure looks BIG when it's fully loaded. If you haven't already bought a pack, have a look at that model or others from the Eagle Creek line. Not sure where you're located, but there's lots of stockists around.
You might find it helpful to lay out all the gear that you're going to be taking, and try a "test run". Hike around your neighborhood for a few hours with the pack fully loaded. That should give you an idea on what size pack you will need. Keep in mind that most people tend to overpack. A lot of experienced Backpackers go by the "rule of threes" for clothing -- one pair on, one in the wash and one ready to go. That may or may not work for you, everyone has to decide what's best in their circumstances.
One bit of advice I've seen is to take HALF of what you originally planned, and TWICE as much money. Speaking of money, make sure you give some thought to that. Are you going to be using ATM's, Travellers Cheques or ? Make sure your ATM accounts are configured with your money in a CHEQUING ACCOUNT with a four number PIN.
As far as which specific items to pack, there's lots of good advice in other posts on this site. I'm sure Kim could provide some good tips. Good luck on your trip, and hope you all have a great time!!!!