Background photo - U.S. #5 Pikes Peak CO.
As with all volcano ascents, the initial portion of the climb is shallow, giving way to steeper pitches as we approach the top - the first two miles gain a modest 501' at 4.4% average (7.7% maximum) grade. The 9.7 miles after the first 2 doubles the grade of the first two miles (8.8% average) and gains 4,441' with no descent (there is not one foot of descent on this 11.7 mile climb). At mile 4.5 we encounter our first major switchback (8 in all as you zig-zag up the volcano). 2 of these switchbacks reach or exceed 20 percent grade during portions of them. The final .7 miles after turning left off Kaloko Dr onto Huehue St is an average grade of 13% (RideWithGPS) and 14% (Strava). However, we have ridden this stretch 4 times and the last time I watched my Garmin the entire way and it never went below 14% and was often at 17% (exceeding 20% briefly) - So, I believe my eyes and screaming quads!
Traffic/Roadway: The first 4 miles of the climb (Hina Lani) is a major artery between Queen Kahumanu Hwy (Hwy 19 that skirts the west side of the Big Island near the Kona airport) and Mamalahoa Hwy (Hawaii Belt Highway) and is busy with fast moving vehicles. However, the road is wide and there is a very comfortable bike path most of the Hina Lani portion of the ride. You are on Mamalahoa Hwy for less than 50 yards before turning right onto Onaona Drive and then immediately left onto Old Mamalahoa Road. Traffic is light for the remainder of the climb and the road is in good condition, although it is narrow with no bike lane.
Descent: Beware of this descent - it can be very hazardous. It is often moist at the higher elevations on the islands and you will definitely encounter very, very steep descents along several of the switchbacks (remember, a couple of them boast 20%+ grades). The road can be slippery - beware of moss which can grow on the road higher up. Be alert and careful on the descent - assess the roadway on your ascend - you will have plenty of time to do so if your climb is anything like ours!
Kailua Kona is a very touristy but mellow Hawaiian town. The prices here compared to 4 to 5-star resort areas with golf courses and their private beaches are very reasonable, particularly in the off-season. Kona is on the "dry" side of the Island, opposite the "wet" side (Hilo). There are many reasonably priced houses and condos along the beachfront that can be rented through VRBO.com. Dining in Kailua is generally informal and reasonable. You can rent road and mountain bikes at The Bike Works in town near the famous Kona Brewery. The Ironman Triathlon course (held every year in August) starts and proceeds through downtown Kona on Ali'i Drive known for its many shops, eateries and bars along the bay.
Finally - Much thanks to author/cyclist Ron Hawks for his photo contributions to this page.
Start (click and drag map; double click to move forward)
Note: Click on “View full route" (top left) which opens the Kaloko Drive RideWithGPS page. Hover over the distance line at the spot you would like to begin a sub-segment for this climb. Click your mouse on the start point and drag the vertical graphing line the distance you wish to obtain sub-detail from, then release the mouse at the end point. This will give you the following sub-detail for the selected segment in the “Metrics” window top right of the page: (a) distance, (b) Elevation gained and lost, (c) max grade, (d) average grade (e) that segment's climb category – e.g. Cat 1, HC, etc., and (f) FIETS score for the segment.
Hover cursor over segment slices, below, for exact grade of a particular segment. Map route (bottom) colors correlate with elevation legend colors.