WARNING! I am giving this cache five Terrain stars. It is significantly more difficult than the average hike in this area. The final quarter mile includes serious bushwhacking, steep grades and exposure to areas of cliffs in lava rock. It is a potentially dangerous hike. Please DO NOT attempt this cache if you are not an experienced backwoods hiker and understand the hazards of such terrain. Ropes and climbing gear are not required, but be sure to carry all the basic survival gear as well as extra water. Long pants, long-sleeved shirts and sturdy hiking boots are a must. Due to many thorny plants, gloves may be greatly appreciated. If you bring dogs, please keep them leashed due to many hidden dropoffs. If you start the hike and don't feel comfortable, turn around - it gets worse!

The photo above shows Saddle Mountain as viewed from 11 miles to the southwest near Highway 26. The peak on the left is the main summit and the end of the very popular Saddle Mountain Trail. The peak on the right is the southeast summit and is the location of this cache. It also completes a triad of caches: Saddle Summit for the main peak, Mid Saddle for the valley between the two peaks, and this cache for the southeast summit.
CORRECTION, January 2017: The above photo is NOT Saddle Mountain! It is Kidder's Butte. Thanks to Orange Crash for the clarification! It sure LOOKS like Saddle Mountain, though!
Following is a zoom lens shot of the TRUE Saddle Mountain from the Astoria Column. The rocky peak on the right is the main summit, the peak in the middle is Southeast Saddle and the peak on the far left is unidentified, but appears reachable by continuing from Southeast Saddle. Click image to enlarge. If you look closely or on Google Earth, you will see that there is actually yet another peak directly in front of Southeast Saddle, with a ridge joining it to the main peak.

The elevation of the main summit is 3,283 feet and the southeast is about 3,260.

The photo above shows the southeast peak from near the summit of the main peak.
Many thousands of people a year follow the Saddle Mountain Trail to the summit of the main peak. It is an easy, but steep, hike along an excellent trail. I am guessing that only a very few climb the southeast peak. The summits of the two peaks are .58 miles apart.
To reach the southeast peak, and this geocache, follow the main Saddle Mountain Trail most of the way to the main summit. When you reach the valley area between the two peaks, you will need to leave the main trail and head east, rather than west. I selected what seems like the best point to leave the trail, and have included it as a waypoint.
You will have only a quarter mile from here to the summit. But, as detailed in the warnings above, it is a very difficult bit of hiking. I pretty much followed the ridgeline, but you will encounter a series of treacherous lava outcroppings along the way. On the way up, I stayed to the left of these and got into some pretty extreme spots. On the way down, I stayed on the other (south) side of most of the rocks, and it seemed a lot better.
Update, January 2017: I believe this is the best routing: At the first lava outcropping, hike up a steep, narrow valley past an enormous root ball and pass to the left of the rocks. On the two subsequent outcroppings, stay to the right (below) them.
The view from the summit is worth it, and I can pretty much guarantee you won't be sharing the spot with 20 other hikers, although you may be able to see them on the main peak. The cache is near the summit and should be an easy find. Enjoy the hike and above all, be safe!