gracygery,
If your path is anything like mine there will be some 'barriers'. For me ones that come to mind are
Somewhere between 10 and 20 miles. This is also tied to 'I can do that road for at least a mile if needed. That is where thigns changed from the same few 'safe' rides to 'I can explore'.
Feeling comfortable going on a 25 mile club ride.
Somewhere between 40 and 50 miles, which was more about the fact teh rides over 40 with my local club were mainly 'out of valley rides' and that meant tehy had some hills.
Anything after that woul dhave to be just getting a lighing system so that 200 miles was doable.