I started at the Go John TH in Cave Creek Regional Park and took the Go John Trail to the NW corner of the park where the Maricopa Trail picks up. I then took that section of the Maricopa Trail over to New River Road and headed back. The map of this trail at http://www.maricopa.gov
shows a trailhead at New River Road, but there was none there that I could see. The nicest section of the trail is just south of Apache Peak, where most of the nearby development is hidden. Just east of Apache Peak there is a junction with a trail that heads north. A couple that I ran into later on who were looking for the Maricopa Trail told me that there is a trail that goes to the top of Apache Peak.
Heading east to west, this section of the Maricopa Trail is fairly easy to follow. It's marked by both yellow tape and the metal "Maricopa Trail" signs. There is a section on private property just west of Apache Peak right before New River Road where the single track trail turns into a jeep road. If you follow the road and head in a southwest direction, you'll run into another Maricopa Trail marker for the next section of single track to New River Road. Going west to east from New River Road, it can be a little trickier to find the trail. Where the single track junctions with the jeep roads just west of Apache Peak, there is no trail marker or tape. There is also an intersection of roads that you encounter before the single track where you have to take the jeep road to the right. I've posted my GPS route of this hike, which shows the official Maricopa Trail along this section.
On my way back, I took the decommissioned section of the trail over to the abandoned mine just off the Go John Trail to get a closer look. It looks like the decommissioned trail also goes further. I think I saw some tailings from the trail on the other side of the hill, but I wasn't sure. I'm thinking there's probably another abandoned mine somewhere not too much farther.