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Hardrock and Osborn Hills Loop Trail

MODERATE 165 reviews

Hardrock and Osborn Hills Loop Trail is a 3.8 mile moderately trafficked loop trail located near Grass Valley, California that features beautiful wild flowers and is rated as moderate. The trail offers a number of activity options and is accessible year-round. Dogs are also able to use this trail but must be kept on leash.

Distance: 3.8 miles Elevation Gain: 436 feet Route Type: Loop

dogs on leash

kid friendly

hiking

horseback riding

nature trips

walking

bird watching

running

forest

views

wild flowers

wildlife

Walk around Empire Mine State Historic Park and explore several smaller abandoned mines and 100 years of mining history Welcome to Empire Mine State Historic Park, home to Empire Mine, which was once the most profitable gold mine in California during the gold rush. This hike will take you around the Empire Mine site and past several smaller mines which were all eventually absorbed as part of the large mining operation at Empire Mine. Along this hike you will see old foundations and rusted machinery covering 100 years of hardrock mining history.

hiking
18 days ago

love this trail to do a quick trail run. few rocks but still a great wide trail. shaded alot. i use it 3 to 4 times a year.

hiking
1 month ago

pleasant for a family hike with kids.

running
1 month ago

Decent running, some inclines for a bit of a challenge. Well shaded.

hiking
1 month ago

Great network of trails! Beautiful wildflowers everywhere.

horseback riding
3 months ago

Drove up there because we had heard the trails were great for horseback riding but when we arrived at 4:15 on Saturday, July 5, the gate leading to the staging area was locked. When we drove up to the visitor center and asked if there was a second staging area she replied yes but the gate closes there at 5 PM. It was a hot day and I can’t imagine people wanting to ride before 5 PM. All other parks we go to don’t close gates until between 8 and 9 PM in the summer. The park rep also said you had to be a member of the local horse club in order to have the passcode for the gate in order to access the trails. Seems odd.

hiking
3 months ago

I always love this trail. One of my very favorites. Today was really crowded as it was a holiday so I took all the side trails and avoided the main one.

hiking
3 months ago

If you are looking for spectacular views or waterfalls, this is not the trail for you. It is a gravel path which turns into dirt about halfway through. Lots of trees, but there are parts that not shaded. Lots of horse droppings along the way. Hard to find- park in parking lot for Empire Mine SP and go towards the end of the parking lot. You’ll see a big gate for authorized cars but there is a walking entrance for people right next to it. Make that first right onto the trail and you’ll pass Orleans Stamp Mill. Continue on that path until you come up to Hard Rock trail on the right. We did get “lost” a few times and had to check the map on All trails. Very lightly trafficked which was so nice! It was 75 today and the perfect weather to explore.

hiking
5 months ago

One of my favorites!

Trail Run

Nice trail. Lots of other off shoots to take. Be careful to stay on the right path

walking
6 months ago

Easy walking in nature with dog. Close to Nevada City and easy to access. Next time I want to take the various options available along the way. Well maintained, easy free parking. Took the garden tour and loved every minute of it - awesome gardens and knowledgeable docents. Next time we want to take the mining museum tour.

Training...Trail run!

Was a fun little training trail run today. First time on this trail...stoked it’s close to home. I’ll be back.

hiking
muddy
6 months ago

Muddy, wear tall socks or pants. The trail is mostly level. The state park was doing some controlled fire burning about a half mile into the trail. Bring your dog on a leash. No need for snacks, good for a long walk or even a trail run. Happy trails!

6 months ago

Hiked it yesterday. Ground soft in so places but well worth some mud on your shoes.

6 months ago

nice with a soggy bottom

hiking
6 months ago

Made several trips here already. Worth it on foot, and I can’t wait to do it again on a mountain bike. So much to see.

This place is amazing. The hiking is free, but you can pay 7$ to enter a little mine museum, and to walk through the old time mine facilities. Hike was great, not very hard at all and I’m a novice. Very cool mine remanence along the way. There are many other trails around this area so you can make this longer if you want. Highly recommend checking out this area. In the winter the museum/visitor center is open 10am - 4, parking was free.

hiking
9 months ago

I hike this trail frequently for a quick 1-2hour trek with my dogs. I love the variety of easy trails and turn offs.

11 months ago

Great walk run bike

walking
11 months ago

As a local, this is one of my favorite walks. Shady in the summer, beautiful in the fall, can be muddy in the winter. Dogs, horses and even lamas have been present on these trails. Near the Empire Mine Entrance is a clean bathroom that can come in handy. I’d recommend this trail to people visiting Grass Valley for sure.

hiking
Thursday, July 26, 2018

I’d say it’s a boring local trail. No views. The loop at some point takes you along the hwy, not very pleasant to walk with the dogs. There’s really nothing to this trail. I see why locals enjoy it: close by, easy. Maybe winter, fall, spring be a little better. Definitely not a summer trail. Park itself is very nice. Definitely worth checking it out.

Tuesday, July 10, 2018

Favorite trail!

Tuesday, June 05, 2018

It can get confusing. Trails are awesone. Vistor center doesn't open till 10 a.m.

hiking
Tuesday, April 24, 2018

Lots to see along the trails.

walking
Friday, March 30, 2018

Nice wide trail, best to walk on weekdays. It gets a bit busy on weekends.

Saturday, February 03, 2018

Nice little hike if you're visiting the mine. Kid friendly.

hiking
Wednesday, January 10, 2018

Great trail to take the kids on! Many pieces of mining history along the trail to explore.

hiking
Tuesday, January 02, 2018

Great trail for walking. Watch out for horse droppings!

hiking
Monday, January 01, 2018

Great in-town hike with varied terrain and loop choices that ring the park grounds. Used by locals daily. You share the trail with fellow friendly hikers, bikers, horse riders, and dogs on leash. Return so you can experience the historic state park gold rush learning inside the gate.

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