So, before all of you used to ride in centuries and the like, you didn't- so I'm looking for advice as I consider my first ever. A friend wants me to sign up for a 104 mile ride from Portland, OR to the Oregon coast. My current riding consists of commuting to work about three or four times a week, five miles each way. I think the longest ride I've ever done in my life is about a third of 104 miles and I thought my legs were going to fall off.
First question is, how hard it is to ride that far when you're body isn't used to that kind of endurance?
Second question is, what is a minimum training routine that I should engage in to prepare for this ride on May 15th?
Thank you in advance for your opinions. I'm sure you get this question all of the time on this forum, so please excuse my asking once again.