Road Cycling - 6 weeks to train for hilly century...Help

I am registered for the Bridge-to-Bridge ride in September. It is a very hilly century and I live in the flatlands of Illinois. I have about 2400 miles in so far this year and have ridden 4 centuries. My average spped on these rides is 18-19mph. I feel like I am fairly strong but I want to make sure the hills don't kill me. What kind of training can I do here in IL over the next 6 weeks that will prepare me for the ride? Any help appreciated. Thanks.

I'm in the same boat. I ride hills twice a week, I find a good hill, ride up it, ride for about 4x the time it took me to ride the hill, and then ride it again. I do this about 4-6 times. Its made all the difference.

Try running up some stairs at a football stadium. Works out the same muscle group that you use while climbing. You may want to post in Training and Nutrition Forum.

I like that idea. Not sure I have the intestinal fortitude to actually do
it, but I love the idea :D You could find a easy hill, ride up one side and down the other a few times. Then you could move on to a slightly tougher one. Cool.

Get a triple chainring and some touring gears too. Bridge to Bridge isn't easy.

You may want to consider taking one of your weekend days and driving to some hills. As we all know, the best way to get better at hills is to do hills. If you have a spousal type, then make a couples weekend getaway into (some) training time.
I live in a place that has some great hills. The way I train on them is to do one of the big ones, recover through the valley as I head towards the next big hill. After a while I can get 4 or 5 of these in a day. The next day is usually an easy (either flat or rolling hills) 30 to 40 miles. In the middle of the week I will do a smaller version of this with one or two big hills and a 30 miler the day after.
Even though it's training, make it fun, 'cuz that's why you ride in the first place. Good luck.