Once you get the century under your belt, you can move up to the Double Centuries (200 miles in one day). We have loads of them out here in California. See www.caltriplecrown.com for more information on Double Centuries.

To train, you should try to increase your weekly and maximum daily mileage by about 10 percent per week. It should take about 7 weeks to double your mileage. Thus it should take about 21 weeks to get from 12.5 miles per day (maximum) to 100 miles per day (maximum), and another 7 weeks to get from a century to a double-century. A good value for the weekly mileage is about 2-1/2 times your maximum daily mileage, although when you get up into the higher numbers, you probably won't have the time to ride 250+ miles per week, so just do the best you can.