You can go on a 2-4 day backpacking trip along the Finger Lakes Trail using the TCAT bus system to get to to the trailhead, and back to campus. Below is a slide show about such a trip, over Fall Break. (SEE PDF BELOW)Here are written directions for three different routes that are possible in the Fall. In Spring or Summer additional routes are possible. (Parts of the FLT close for hunting in the Fall - always check.) Make sure to check the bus schedule which varies by day-of-week and season.
You could take the 65 bus from Cornell, all the way out to Danby. (Get off before the bus turns right on S. Danby Rd.) Then walk about one mile further out 96B, to hit the Finger Lakes Trail. Hike in about one mile (but steep) to the Tamarack Leanto. Next day you could hike South and West along the FLT, or branch off to do the Abbott Loop. Then end up at the Chestnut Leanto. The third day, you have just a short hike to Bald Hill Rd, and then about two miles of road walking to get to Rt 96B in Danby. There, you can flag down the same 65 bus inbound, and take it all the way to Cornell. BUT, the catch is that this bus does not run on Sunday. AND, on Saturday, there is a limited schedule that departs from downtown, not Cornell. So, could you leave on Saturday morning and return on Monday?
A second possible route: Take the 43 bus out to Dryden. The bus actually crosses the Jim Schug Trail. Take this East about 2 miles until you intersect the FLT. Take this East and South until you enter the Hammond Hill State Forest. Unfortunately, this short stretch of the FLT, from Jim Schug to Hammond Hill, runs along roads. Once you are in Hammond Hill you can camp anywhere. But, there is no leanto in this state forest. Continuing South, you enter Robinson Hollow State Forest, where there is the Kimmie Leanto. From there it is just a short hike out to Route 79 near Caroline. This trail crossing seems to be just about at the very end of the bus route 52, which you can take back to Ithaca. The 52 bus runs only on weekdays and Saturday. I see that the 43 bus only runs on weekdays, and service to the little loop that crosses Jim Schug is quite limited. Outbound it only takes that loop in the late afternoon and evening. While inbound, it takes that loop in the morning. Hmmmm. Less than ideal!
But, this all could work if you take the bus out on Friday afternoon. You don't have to hike too far before you are in Hammond Hill, where camping is legal. Then, hike for two days, camping at the Kimmie leanto on Sunday. Then come out on Monday morning, and take the 52 bus back.
Or, From the end of the 52 bus line in Caroline, you could do an out-and-back (going North, initially) into Robinson Hollow SF and then into Hammond Hill. Again, you would not have bus service on Sunday for out or back.
Third route: You could take bus 67 to the point where the FLT crosses Route 13, near Treman SP. There is the Sierra Shelter in Treman park, maybe half a mile in. You need to check that this shelter is open in this season (call DEC). Following the trail West from there, you come to a bivouac area near Porter Hill Rd. That looks to me to be about 7-8 miles. From there it is a short walk out to Route 327. Go North on 327, maybe 1.5 miles, and you come to the very end of bus route 20. Again, we must look at the bus schedules. Ah ha! Both of these buses run on Sunday. So, you could do this hike in either direction, from Friday to Sunday. But, the service is quite limited. Notice that this route only has one long day of hiking -- and there is no legal camping between the Sierra Shelter and that bivouac area.
If you wanted to make this hike a bit longer, you could take the 65 bus, mentioned above, and get off at Comfort Rd. Then walk down Comfort Rd about half a mile, to pick up the Buttermilk Falls Spur (you MUST check to make sure this spur section is not closed for hunting.) Heading West, the Buttermilk Falls Spur intersects the main FLT. You turn right and follow the FLT North, and then West to the Route 13 crossing mentioned above. A short hike further and you are at the Sierra Shelter. From there, follow the directions above.This map shows five TCAT bus routes in relationship to the Finger Lakes Trail, state forests, and nature preserves. (click to enlarge)