Begin the hike on San Ysidro Trail at the sign. Stay on the trail and off of private property.
At 2 tenths of a mile, join paved road. Turn left. The trail parallels the road in some spots, or you can follow the road. You may see a chain-link gate across the road. It is more polite to find the trail to the left of the road and bushes rather than go through this gate.
The pavement ends and the dirt road begins with a heavy gate. There is also a trail here to your right called the Old Pueblo Trail. Continue through the gate and follow the dirt road.
At 1/2 mile, you will see a junction with McMenemy, marked by a sign. The sign will say "McMenemy - Lower" on it.
Immediately cross the creek.
At about the .6 mile mark, there is a fork. Don't go right. It dead ends.
At .75 you might see a fork where it heads to a gravel road on the left. Don't go left to the road.
At just under a mile, you start the endless shallow switchbacks. Many have cut them leaving a maze of confusion.
At 1.3 miles there is a trail sign. Not sure why there needs to be a sign, but perhaps it is comforting to know you are still on the trail. Anyway, at the sign, go right.
At the 1.5 mile mark is the junction with the Girard trail. There is a nice rock bench and a hitching post. Makes a nice destination if all you wanted was a quick, short hike.
At this spot, McMenemy trail goes down hill a bit. At 1.5 miles you should see a water tank on the left if you went the right way.
After a while it seems to get a little prettier. At 2 miles there is a small spring. I don't know if it is there all year, but it was there in April when I wrote this up.
At 2.5 miles there is another junction. There is a gate and a sign. Turn left to go to the Hot Springs trailhead on a well-maintained trail. Turn right to go to Saddlerock and toward the N. Vincent trail. Are you noticing a pattern yet? Trails named after people, and one plaque spotted on the rock bench so far. Anyway, turn right toward Saddlerock. You'll notice that the trail here is quite steep.
At about 2.75 miles you'll reach the summit. There's a big rock and arrangement of rocks that on this occasion was shaped as a heart. Saddlerock is the name of the big rock. This is another good spot to turn around if this is as far as you wanted to go.
To continue on, take the trail to the left of Saddlerock (as you are looking toward the mountains, although I suppose by now there is a trail on the right as well.)
At roughly 3 miles, you'll reach the power lines. At this junction you could turn left to go to the Hot Springs, but then you would be trespassing and that would be wrong. If you turn right, you will return to the San Ysidro trail. We're going to turn right because we are obedient.
At about 3.25 miles, turn right on the Girard trail.
At 3.68 miles, after descending through a lush section (at least in April it was lush) that becomes rocky, there will be a prominent fork in the trail. Steps lead off to the left to a plaque on a rock. Actually, it's a plague of plaques. There were three of them when I last looked. There are lots of rocks there, so plenty of room for more plaques. I get quite annoyed that people feel they can't donate money without a plaque being placed somewhere or a hospital wing being named after themselves. But that's what happens when you live among the wealthiest people in the world. They run out of places for plaques and have to start spamming the trails with them. It's like billboards on the freeway to me. Well, enough of my commentary... The trail we want is to the right.
At 4 miles we are back to the rock bench and hitching post. Take the left fork to return along the trail you originally started on. This hike is not quite a loop. It's more a figure 9.
At the 5 mile mark, you cross the creek and are back to the original McMenemy sign.
At the San Ysidro trailhead, it's about 5.5 to 6 miles total.