http://www.everytrail.com/guide/easy-hike-to-black-hole-of-calcutta-falls
Location: Cool, California
Fee: No
Access: Family Friendly • Dog Friendly
Distance: 2.1 miles (RT) / 3.4 km
Elevation: very little change
Season: April
Difficulty: Easy
Directions: From I-80 at Auburn, take the Hwy 49 exit, and drive south on Hwy 49 for 2-3 miles to the where Hwy 49 forks. Turn right towards Cool. Cross over a bridge and Gate 150 is one your right hand side. Parking is limited on the side of the road. There is also parking located staight at the fork in Auburn Confluence, but you will need to walk about 1/4 mile. Show up early to get a spot.
Easy, dog-friendly- 2.1 miles roundtrip that took around 1-2 hrs.
My boyfriend, cousins, baby husky, and I went on a hiked in July thinking the weather would be suitable. Boy, were we sweating! We arrived around 11AM with the blazing sun above us. I recommend going in the spring time around April for a cooler hike and a bigger waterfall.
Arrived at Gate #150 (11AM) in Auburn State Park. Park along the side for free. Doggy-bags were available at the gate. We walked shortly on the gravel until we reached the bridge you see in the photo. American River was under us and on the way back we saw a lot of people sunbathing and playing in the water. We continued walking on the flat dusty road until we reached the waterfall, but in the summer time, it’s more of a stream. It’s a nice photo-op. Baby husky didn’t want to leave the cool water.
At this point, you can decide to either hike back the same way you came or continue hiking to the rangers station then walk back. If you continue, it’s an upward hike. We walked for another .5 miles before we decided to head back since the baby husky didn’t seem to want to walk anymore.
I recommend bringing 2-3 bottles of water per person. Once you reach the waterfall, head back and go down to play in the clear American River. Tons of hikes in the Auburn area, but due to the drought, everywhere is low water level.