Summit Elevation (m): 2,766
Elevation Gain (m): 1300
Total Distance (km): 28.00
Total Time: 8:00
Difficulty: Hiking (Easy scrambling, long day, minimal scree)
Water Available: Rockbound Lake and above lake in glacial stream
Cell reception: Reliable at Summit, none on approach
Rating: 4/5 due to the long and tedious approach, the first 9km to Rockbound Lake are also very boring. After the lake the route opens up and you have stunning views, but the summit is still far off. Once at the top of Castle Mountain, it is all worth it as you are greeted with fantastic panoramic views.
Turn off of the Trans Canada at the signs for Radium and Castle Junction (Hwy 93). Head North over the bridge and past Castle Junction. Turn east (right) on Highway 1A, shortly after turn left to the Rockbound Lake parking lot.
After the 8.5km to Rockbound Lake, follow small cairns around climbers right to find a trail that follows an avalanche gully to the rock band above. Gain the rock band and follow the trail over a small hump. From here you lose a little elevation, follow the odd cairn around the bowl/upper rock band to summit, picking up cairns as you go. Generally try to stay higher up, not right on the edge of the rock band. Optional descent is taking a prominent gully to the lower rock band. This can also be used as an ascent route and is probably faster!
With plans to originally summit the beautiful Nigel Peak, I quickly changed my mind just past Banff when Castle Mountain came into view. I had almost forgot about this majestic ridge, which I have wanted to camp on for awhile now. I knew the weather wouldn't be great if I was to sleep on Nigel (forecast called for about 5mm of rain), so when I found out that the skies around Castle would be clear all night I quickly turned off the highway and went for it!
This was my first time doing Castle, and while the gigantic Rockbound Lake is beautiful, and the old glacier basin stunning, the hike is tedious. It's not difficult by any means, it is only discouraging to be a couple hundred metes below the summit on approach only to walk away from it for a few kilometers! Once above the lake it is a very peaceful stroll around the worn out glacier basin, until you reach the last kilometer where you need to crawl up some scree.
The summit views are incredible, as you can see all the way up and down the Bow Valley, as well as down Highway 93 into Kootenay National Park. Assiniboine dominates the skyline in the South, while Temple, Deltaform, and the other 11er's in the area dominate the North. I found a suitable nook just below the summit and set up a small bivy site with a wind wall, which fared well in the 40km/h winds. The only downside was waking up to a hungry pika chewing through the brim of my hat!