f1geek said:
If you do the math, you'll find that lifting the car 5000 feet is equal to about 6.5 kWh.
Anecdotally I see a 1.7 miles/kWh consumption rate when I drive 4.5 miles with a 1,000' elevation gain to the park where I frequently hike with my dog. That works out to around 2.6 kWh for the trip. Assuming that 4.5 miles on level ground takes 1 kWh then 1.6 kWh was used for the 1,000' climb.
For a 23 mile, 5,000' climb:
Elevation gain: 5 * 1.6 = 8 kWh
Distance: 23 / 4.5 = 5.1 kWh
Total: 13 kWh
Still, it should be doable if starting at the bottom with a nearly full charge since a lot of energy will be recuperated on the way down. In my case the 9 mile, 1,000' up/down round trip from home to the park nets ~4.4 miles/kWh.
Edit:
I checked a route from Highland to Lake Arrowhead on evtripplanner.com. There isn't a choice for the e-Golf but using "Nissan Leaf (beta)" its calculation is very close to my back of the envelope math:
Distance 21.3 miles
Total Energy Used 11.1 kWh
Average Efficiency 520 Wh/mile
Net Elevation Change 3897 feet