If you start at Hellman Park and hike to the white or green water tank, it's about 4 miles, round trip. If you hike to both tanks, it's about 6 miles, round trip.
4.37 miles more or less
The entire trail is about 15 miles long broken up into sections. Take a look at the map at the beginning of Hellman trail off of Greenleaf.
About 4 I think
Hellman is more of a starting point. The trail is part of a interconnected network that can get you all the way to Carbon Canyon. Within the Puente Hills Preserve, it is only a few miles.
Around 4 miles or so,give or take
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