If we're talking about getting out to Tanner Butte, this is a most excellent hike. Views from Tanner Butte are fantastic. So much within the gorge itself, Benson Plateau, Chinidere, Defiance, and then Mt Hood, Mt Jefferson, Mt Adams, St Helens and Rainier.
There is reliable water as you start up Tanner creek trail. There is another water source about 3 miles in. I have never seen it dry but that's your call. No other water on the trail. The first few miles are a march up a moderate, but unrelenting ascent. As you start to top the mountain plateau it’s a mile through thicker cover, expect blow down. Then a few more miles through ‘Bear Grass Alley’. The stuff can get thick and trip you up.
The cairn marking the side trail isn’t always obvious, maybe mark it on your GPS. It’s up the side trail a very steep 1/4 mile to the top.
From the Eagle Creek trailhead it clocks in a hair over 20 miles. Love this hike.
Having just completed the hike up to Tanner Butte I have a few comments for those considering the hike. According to my Oregon 600 GPS it was a 19 mile hike out and back from Eagles Creek parking lot,. This is the parking lot at the fish hatchery not the one at Eagle Creek trail head. The elevation of Tanner Butte is 4,500 (Green Trail Map 428C confirmed with GPS) the elevation at Eagles Creek is 60 ft, hike elevation gained 4,440 ft. (GPS confirmed). It may be 3,349 ft. for the trail head but you have to get to the trail head which ever option you use to get there.
There are six options to the Tanner Butte trail head (trail #401) my own favorite is Eagle Creek/Stairs to the west along bike track/Cut off just passed stop sign/Up road 777 the distance by GPS is 1.23 miles. The trail head coordinates are N45° 37.573' W121° 56.601' these are different from those provided on the companion map. The coordinates on the map are those of an end point of the Tanner Creel Cutoff (trail #448). The end points of this trail are 4.5 miles up the Tanner Butte trail and 3.0 miles up the Tanner Creek trail (trail # 431). It is well worth noting that if you use the Tooth Rock Trailhead option it has the higher incidence of car prowling than other nearby trailhead. Whichever option you choice it is anything between 1.6 and 1.0 miles with elevation gain of approximately 1,100 ft.
As for the hike from the trail head you steadily climb to 2,700 (elevation gain of 1,770 ft.) in the space of 2.3 miles, at which point you reached the start of the ridge that will run up to Tanner Butte. For the next 2 miles you will gain 1,000 reaching the Tanner Creel Cutoff (trail #448) on the left and the trail leading down to Dublin Lake to the left. You will continue to gradual climb until the trail until it levels of which is followed by a very gradual descent to a saddle before rising again to the cutoff for Tanner Butte. The cutoff has no sign post however it is marked with a cairn of stones in the middle of the trail. From here it is a half mile of very steep ascent to the top and Tanner Butte’s magnificent unrestricted 360 degree view.
I left Eagles Creek at 7.10 am was back at 4.18 pm however though a regular hiker I am 71 years young. I am sure those that are younger will be able to achieve in a shorter time.
Where ever you are enjoy your trails and if you are ever up the Columbia River Gorge or surrounding area maybe we will meet on the trail.