50 miles is a milestone! 3 1/2 hours in the saddle is a milestone!
25 miles more to 75. That is 50% more miles. Break it down into manageable chunks with adequate breaks. When the miles get tough (your last 5 miles) may be a time for a little look at the scenery... Riding more frequently might be as beneficial as riding farther less often, now that you know 50 is a breeze.
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