A hidden gem! The trail head was very unassuming as there was some graffiti, but once you go back the trail it is very beautiful. The trail goes up the hill along a creek and within moments you feel as though you are deep in the woods. It rained the day before, so the trail was wet and the creek was flowing strong. There were some fallen trees that I had to climb over/under. It was a little treacherous from the rain and slippery at parts and I actually wiped out climbing on one of the downed trees. There is a spot where you will need to cross the creek via a board and some rocks. It wasn't obvious to me at first and I went to the left and up the hill on another path.
After crossing the creek, you will continue hiking alongside it for about another 1/4 mile until you intersect another wider path. This takes you to the top of the hill. Near the top, there was a lot of water from the rain that blocked the main path, but there was another way around. The top of the hill offers great views of the entire east bay and peninsula.
Overall, this trail was a lot of fun. What it didn't offer in distance it made up for in adventure. I would rate it moderate as there is a significant climb to the top and the path is very narrow at parts. One wrong step could make for a bad day.
Something noteworthy is that Leona Heights Park is operated by the city of Oakland and not by the East Bay Regional Park District.
Really nice trail. Very kid-friendly. The slope is generally nice and easy and there's lots of shade.
One thing to note: this trail does not require dogs to be on-leash. 50' in to the trailhead if you're starting from the apartment complex end, there's a sign that clear says it's a dogs-off-leash trail and then it has some rules about dogs needing to reply to voice commands.
Not a huge deal, but wanted to put that out there.