As far as I'm concerned, "hill" is inaccurate.  The thing ahead that looked hill-like was not the summit, and JR kept pointing that out but I refused to acquiesce.  He turned out to be right.  Fortunately he was a gentleman about it and only brought up how right he was 6 or 7 times throughout the rest of the day.

The hike involved a shuttle of about 15 minutes, with one vehicle left at the end of Synder road and the other at the end of Ft Lowell road.

You drive as far as you can go on Ft Lowell road and it ends in a lovely little paved parking lot, from which it is a 3-mile hike to a saddle that leads to AC Hill. I was wearing three layers, including my wind-resistant bicycling jacket...and was also donning a winter knit cap.  JR had only a thick T-shirt, but he's from Alaska. Within 45 minutes of climbing up the trail, I had taken off the jacket and replaced the knit hat with a baseball cap.  The temperature was supposed to be 55 and it turned into an ideal hiking day with just a minor chill at our highest point, where it was breezy and 2,000+ feet higher.

The gradual climb to the saddle begins in cactus terrain on a well-maintained footpath. For the first half hour or so you can still see several high-end homes down below but pretty soon there are no more sights or sounds of civilization.The trail climbs moderately the whole way, with two dips down into drainages, the first after maybe a half hour.The trail eventually flattens out more dramatically at the second drainage in what seems to be a dry pond. . .then continues to the right.  At the point, we approached what JR calls "the wall" which was steep climbing for no more than a 1/2 mile.  After that comes the saddle, which is clearly marked.  As you ascend, cactus gradually gives way to tall winter grasses.

The trail is piled with a lot of baseball-sized rocks in places which makes for a lot of walking with eyes focused downward.  

Once we reached the saddle, the trail we would eventually take to our shuttle car descended ahead of us; we turned to the right to attempt climbing to Agua Caliente Hill.  The trail sign posted at the saddle read 1.5 miles.  At this point I wanted to go all the way to the top because I was not yet very tired, and I thought I could handle 1.5 miles - even though I had been warned by the Internet and other hikers that it was very steep.  JR was less enthusiastic.  Tim was willing to try a little ways.  We decided to go at least far enough to get a view of the peak.

Not long after starting up, the trail became as steep as any section so far; we trudged slowly and had to stop periodically to catch our breath.  Within about 15 minutes, it got preternaturally steep and I thought "uh-oh, we haven't even reached the 'steep' part yet."  All the while I was gazing up at a lovely, near-symmetrical, cone-shaped peak with some rocks on the top, all set about with yellow grasses, thinking that was our destination.  It looked like it would be about 1.5 miles from the sign. But after another 1/2 mile of rocky incline-hell, the trail gradually leveled out and scooted us around to the right of the peak I had been eyeing.  And, I had to admit (silently, to myself) that JR had been right.   After passing this false summit, we saw that the trail just kept going, far into the distance, with a rocky outcropping perched high above us, which must have been AC Hill.  

We stopped in a flat area and ate lunch.  As we were munching away, a hiker walking a poodle came by and we asked him if was heading to the top, and he said yes, then pointed out it was actually 2.2 miles by GPS to the top, and he was hoping their wasn't any snow up there.  I found this somewhat comforting.

As we started down I realized how tired I felt, not to mention kinda sore, so was glad we turned around when we did (plus it was already 1pm and it would've taken us 2 hours to get to the top then back to the saddle).  We descended back down to the saddle where we met a woman with her teenage daughter, and JR gave them information about the hike.  Then we headed down (forward).  

This new trail took us along several ridges with wonderful views . At certain points it felt like you were walking on the edge of the world.  The canyon fell away so sharply it was nearly dizzying.  For JR and Tim, both of whom have vertigo with heights, there were no side trips to peer over the edges.  The very rocky trail gradually descended as it meandered along the edge of a ridge overlooking Agua Caliente canyon.  The vistas were spectacular and the plant life much more varied than the first half of the hike. The very last bit included an extremely steep, rock-strewn descent into AC Canyon, then a mile or so of flat walking on a narrow, sandy trail to a paved road that led to JR's truck.

We think we hiked 9 miles, or close to it, in 5 hours.  It sure felt like 9, anyway, but could have been closer to 8 since I am not certain how long the section of trail from the saddle to the shuttle car was.  I'd like to try again with more time to get to the top.  The whole hike would be 10.4 miles: 3 up to the saddle, 2.2 to the summit -- and back by either route.  Although this is a strenuous hike, it is a beautiful mixture of desert and grassland, and the views are well worth it.