My goal Saturday morning was to do an out and back to York Springs, which would put me on Old US 15, which is then a straight shot to Gettysburg. I’ve been looking at Gettysburg as either a longish (75 mile) day ride; or as a possible camping expedition.
What I discovered, at least on this ride, is that you can’t get there from here. Google maps and Ridewithgps show crossing new US Rt. 15 in Latimore Township on Old US 15. The problem is that new US Rt. 15 is a divided highway in this area with no break in the barrier. In order to cross, one either has to lift the bike over the guide rail while 60 mph traffic is whizzing by in both directions; or backtrack a few miles to another intersection and then ride back down to the Old 15 “crossing.” Since I only had a cue sheet and no map, I wasn’t up for trying it. I figured I was about 2 miles or so from York Springs.
Coming back and looking at maps, it does look like I can either take a bit of a detour and ride along new Rt. 15 for a mile or so; or I can take a slightly southerly turn from this intersection and come into York Springs from a different direction.
All was not in vain, though. I ended up exploring the Latimore Valley Fairgrounds, which appears prime for stealth camping. There is already an RV site (can’t seem to find any info on that), and plenty of grassy/wooded nooks to pitch a tent in privacy.
So depending on my schedule, a regrouped attempt on Gettysburg may be in the works (very few hills btw); and possibly an overnight camping adventure.
Distance: 40.4 miles 2010: 838.8
Pedalling Along 
You can cross 15 in York Springs and take BikePA route J2 from there.
http://opencyclemap.org/?zoom=14&lat=39.9914&lon=-77.12137&layers=B000
Yea. It actually looks like I can turn left (south) onto Plank Road, and then turn right and come into York Springs from the south.