Mt Lamarck (4090m) is easily climbed from the North Lake trailhead via the Lamarck lakes.
From Bishop take 168 west (also marked as West Line St) almost all the way to the end. The North Lake turnout is on the right handside just before the Lake Sabrina campground. The road to North Lake is only 3km and mostly unpaved. The only way to leave the car at the North Lake trailhead is to take a campsite for two nights; otherwise you have to leave the car at the hikers' parking lot, about 1.5kms before the trailhead.
The North Lake trailhead splits almost immediately: the main trail goes up towards Piute Pass, the left trail goes to the Lamarck Lakes. Turn left towards the Lamarck Lakes. You will cross three bridges. There is another tricky fork: about 30 minutes into the hike, if you go straight you'll end up at Grass Lake. The junction is well-marked but in the dark it might not be obvious. You have to turn right towards the Lamarck lakes. Then in about one hour from the start you reach the lower lake. At the unmarked fork, go left and cross the creek. Continue following the trail.
Just before the second lake, a sign "Trail" sends you to the right side of the creek. In a few minutes you have to cross back to the left side but (as of 2016) there is no sign to tell you so: the trail continues and the only signs (virtually invisible in the dark) are some dead branches on the trail that imply "the trail stops here" and a big cairn on your left. (If you keep going on the trail, it dead ends almost immediately). There is a trail on the other side of the creek: just look carefully 50 meters before the lake. If you miss this crossing, you get to the second lake, and that's a bad sign. Cross wherever you can, and start ascending and hopefully you will find my ancient cairns that will take you to the trail on the other side of the little hill. Even if you found the trail that ascends the hill, it is tricky to find out what to do when that trail disappears. There is a very good trail on the other side of the hill, but it is not trivial to find it. You may have to scout a little bit. The trail does not head straight for Mt Lamarch, but heads south, via steep switchbacks, over a nice pass. If you don't find this trail a nd you get completely lost, just ascend the left bank of Lake Lamarck 2. There are several easy chutes. From the ridge you will probably see the trail on the other side. (The trail physically turns around the left side of the mountain that towers over Lake Lamarck 2's western tip, but getting there off-trail implies a lot of bouldering. It may look like a shortcut on the map, but it will take you a lot longer).
If you find the trail, it is easy to follow it. After the pass, it enters a canyon and follows it to the plateau and bowl of Mt Lamarck.
There is no particular route to climb Mt Lamarck. Just follow whatever seems easier. At the top you are on a broad plateau. There is a rock that is obviously the highest point and that's where the register was in 2016. Unfortunately, the real summit is not there, but someone decided to put the register there and save you 15 minutes. Look west and you will see the other peak, which is obviously higher. To get there, there is an easy connection that goes around the gap separating the two peaks.
Note that you don't see Darwin Canyon from Mt Lamarck because the slopes going down to Darwin Canyon are not steep enough.
You can descend Mt Lamarck back to the bowl any way that looks safe. There is a little glacier and snow field below the mountain. Lamarck Pass (usually referred to as "Lamarck Col") is a famous pass that connects the Lamarck Lakes with the Darwin Canyon lakes. Lamarck Pass is tricky to indentify on both sides.
Lamarck Pass from the north:
Lamarck Pass from the south:
To bypass the ice/snow, there are two easy ways. One is to simply climb the
gentle moraine to the left even before you arrive to the bowl. The other one
is to climb higher up the promontory to the left. When you arrive at the bowl,
stay about 10 meters higher to your left.
I'll describe the route to bypass the ice coming down from Lamarck Pass because it is usually downhill that one gets more intimidated. From the pass, walk down just a few steps and start traversing to your right. Walk through a notch and downclimb into the first chute (a little tricky, but this is the only difficult part). Then stay at approximately the same elevation and climb the other ridge of the chute. Climb up this second chute and climb over its other ridge. Now downclimb into this much gentler chute or, if there is still ice even in this chute, traverse one more chute: the chutes get gentler and gentler as you keep moving in the same direction. In fact, going this way is a shortcut of sorts even with no snow.
When you reach the top of
Lamarck Pass (almost 4000m) you are welcomed by the sign of the Kings Canyon
national park and you have a great view of the lakes of Darwin Canyon,
Descend into Darwin Canyon moving slowly to the left (east) until you reach the crest that connects Lamarck Pass to Mt Darwin. There are three main "depressions" on that crest. The first one is too steep, the third one usually has ice. The second one leads down to the Schober Lake in the most gentle manner.
Coast the three lakes to the left and you will soon reach the next lake, Bottleneck Lake, and then about 30 minutes later the two Fishout Lakes (you will probably have to stay higher than the lakes). Then drop down rapidly towards Sabrina Lake. There is a trail along the western shore of Lake Sabrina that is rarely used. Keep descending (possibly bushwhacking) until you hit the trail, which mostly runs about 100 meters above the lake. This trail takes you to the boat landing and parking lot.
Getting from Lake Sabrina back to North Lake takes about one hour but you have good chances of hitching rides once you are on the paved road.
Video from Mt Lamarck
Pictures of this hike
View from Mt Lamarck
Weather forecast for Mt Darwin and Mendel