Astro Tower (Half Mtn)

Half Mountain forms the terminus of the extensive north ridge of Longs Peak. Its west face rises 1,600 feet above Mills Lake. The summit of Half Mountain is seldom visited but the steep buttresses jut below to the south are of interest to climbers. The largest and most striking of these buttresses is Astro Tower.

This page has trip reports for two visits to Astro Tower, about a month apart. Astro Tower was a great place to head when other climbers were beginning to flock to other sunny and dry walls such as the Petit Grepon and Saber. The only hitch was that we had to enter the gates before 5am in order to bypass the timed entry in the Bear Lake Corridor. But given the relatively quick 2-hour approach to Astro Tower, the fact that the wall is not in the sun until late morning, and the short climbs, there was no need to start hiking so early. We solved this dilemma by loading the mattress in the back of Nate's truck so he could take a 2-hour nap while I studied for an upcoming analysis preliminary exam; and after this proceeded to enjoy a leisurely coffee and breakfast at the trailhead before heading out for a day of climbing.

On our first trip up to Astro Tower in June 2021, we started off my climbing The Kimball Route (3p, 5.10-), a nice route that Nate and Scott Kimball had put up years ago. While climbing this route we spotted a nice looking line to the right, so after topping out, we descended back to the base of Astro Tower and climbed back up, putting up a new 3-pitch 5.10- route which we called "Arganegg". We had the entire crag to ourselves, the rock was sunny and high quality, and the sweeping views of Glacier Gorge were spectacular.

On our second trip up to Astro Tower about a month after the first trip (and done in the same style of taking a morning nap/study session/coffee/breakfast at the trailhead), we climbed Space Walk (4p, 5.11a), a great 4-5-pitch route up the center of the wall.

The following page gives a route overlay and photos from the three climbs I have climbed with Nate on Astro Tower.

Route Overlay for Routes I've Climbed on Astro Tower

Approach Photos

Approach

2nd/3rd

Starting from Glacier Gorge trailhead, hike as for Glacier Gorge, but at Mills Lake cut uphill up left and climb through forest and talus up and rightwards to the tower. It is best to hike to just above the left side and make a single rappel from an obvious notch (off a fixed nut) to the base of the west face to access the routes. The approach takes roughly 2 hours. On our first trip to Astro Tower, Nate and I hiked out to the east to intersect the North Longs Peak Trail, to see if this was a better way to approach/deappraoch. We concluded that this way takes longer (it took us 2 hours 6 minutes to hike out) and that the standard west side approach/deapproach up from Mills Lake is best.

Getting in a couple of hours of studying in the Glacier Gorge Parking Lot before we hiked in.

Breakfast in the Glacier Gorge Parking Lot.

Hiking.

Reflection of Glacier Gorge peaks in Mills Lake.

Talus approach.

Some pretty trees on the approach.

Primrose.

The rappel is at the obvious notch.

A single rappel to the base of the west side of Astro Tower.

The single nut rappel anchor.

A view of Spearhead and Chiefshead.

Steep golden granite.

Relaxing at the top of the route before hiking out.

On our first trip to Astro Tower, we decided to try to hike out to the east and intersect the North Longs Peak Trail. Lots of krummholz.....

Cool tree on the hike out towards Longs Peak Trail.

A bit of 'shwacking to get to the North Longs Peak Trail.

Finally...the North Longs Peak Trail!

The river above Alberta Falls, as seen from the North Longs Peak Trail.

On our second trip to Astro Tower we took the standard descent that reverses the approach from Mills Lake. This was is the best way.

Pitch-by-Pitch Photos

Kimball Route aka "Arganimball" (5.10-, 3p)

Date: June 13, 2021 Partner: Nate Arganbright

This route was put up by Nate and Scott Kimball several years ago. The Rossiter guidebook gives no description for the route other than to mention its existence as the "Kimball Route" (which Nate renamed to "Arganimball" to represent both members of the FA party, especially considering that Nate had led the FA). The route is on the far left side of the west face, and the first pitch splitter is immediately obvious from the base of the rappel. The rock is good and the climbing is fun.

Pitch 1

5.10-, 80'

Climb the obvious splitter, which goes from fists to squeeze chimney. Belay on a nice ledge above the splitter.

Obvious splitter of Pitch 1.

Nate starting up Pitch 1.

Pitch 2

5.10-, 115'

Climb the steep handcrack on good rock.

Great crack climbing on Pitch 2.

Pitch 3

5.8, 115'

Continue up featured rock and cracks to the top.

Nate starting up Pitch 3.

Finish of Pitch 3.

"Arganegg" FA (5.10-, 3p)

Date: June 13, 2021 Partner: Nate Arganbright

Nate and I spotted this line while climbing the Kimball Route. It was pretty good climbing with a nice roof traverse to finish off the route.

Pitch 1

5.8/9, 100'

Surmount the bulge and climbs cracks to a belay. This is the same belay as at the top of Pitch 1 of the Kimball Route.

The base of Astro Tower, left side.

Looking up at Pitch 1.

Pitch 2

5.8/9, 115'

Continue up cracks.

Looking up at Pitch 2.

Pitch 3

5.9/10-, 115'

Climb the corner crack up to the roof, then make a hand traverse left under the roof to join the finish of the Kimball Route.

Looking up at Pitch 3.

Space Walk (5.11a, 4-5p)

Date: July 11, 2021 Partner: Nate Arganbright

This steep route ascends cracks and dihedrals up the southwest corner of the buttress. Generally the rock is quite good and the climbing is varied and fun.

Pitch 1

5.9, 75'

Begin below the smaller of two left-facing corners that arc up to the left. Work around the left end of the corner/roof and follow a crack to a ledge.

Looking up Pitch 1.

Pitch 2

5.9, 100'

Climb the left-facing dihedral above. There are a couple of variations for this pitch. From the initial dihedral, we continued directly up a nice corner to a pedestal on the right. It is also possible to head rightwards a bit to another dihedral and belay at the same pedestal which is now on the left.

Looking up Pitch 2.

The corner variation of Pitch 2.

Pitch 3

5.9, 70'

Tackle a one-inch crack in the right wall of the big dihedral and belay on a small ledge.

Looking up the splitter.

Pitch 4

5.11a, 70'

Climb a steep corner with a thin crack. Set a belay on a small ledge (we did) or continue onto Pitch 5.

Nate starting up the crux Pitch 4. Nice lead!

Pitch 5

5.10c, 80'

Traverse up and left to a sloping stance and jam a flared crack to a roof. Traverse left beneath the roof until it is possible to exit straight up. Tread lightly around some giant wedged blocks near the top.