At 8:00 AM I was the first to this trail head, which is really just a 4-5 car plot of land in front of the yellow gate.  You can see that beyond it will someday be a proper parking space, where the current kiosk is.  The trail was almost entirely empty, I met 2 groups on my way back down.  There were wild huckleberries along the path, some ripe enough to eat.  The final 0.25 mile or so is very overgrown, wear long pants and a long shirt for comfort (I didn't, just a minor annoyance).  The view from the summit was spectacular, partly from the sheer peacefulness of no one else being up there, but the view really is great.  This is a gem of a trail,

I hadn't been to Index before and I really enjoyed the views along the river after my hike.  Keep driving down Index-Galena Road after your hike and you'll get some great views:

Got there just before 9:00AM on a sunny Saturday and were the first ones there. We weren't even sure if we were at the right place because it was so lonely! Parked in front of the white gate. Once there, walk through the grassy lot to the trail entrance marked by an orange cone. 

We were scared about encountering a bear since it was so lonely but didn't see any wildlife other than birds and a snake. 

The hike itself was great. Short and fairly easy with a rewarding view for it's length. There were also markers for every 10th of a mile which is always nice. It is pretty overgrown for the last .4 miles. We got the top to ourselves for about 15 minutes or so and then another group arrived. On our way down we encountered about 5 other groups. Back at the gate, there were 4 cars including hours.

In total we spent almost exactly two hours there, with roundtrip hike + stopping at the top for at least a half hour.

Arrived at the trailhead around 10 AM on a Saturday morning and was able to get a parking space at the gate. The parking lot has not been completed yet so there is parking for about 3 cars at the gate to the trail. If you drive a little past the gate on Index-Galena Rd and take your next left into Index there's more parking and it's an easy walk across the bridge to get back over to the trail. We only saw a handful of other parties on our way up and it was a short, sweet hike ending with a beautiful view of the Cascades and Bridal Veil Falls. The foxgloves and daisies were in full bloom along an entire section of the trail and the trail was overall well maintained. On our way down we saw a lot more people on their way up so I'd recommend getting to the trailhead earlier if you want to avoid crowds. I'm sure once the parking lot is complete and word gets out about this trail it will be much busier. 

This is a really enjoyable hike. It was not crowded, but I imagine as word gets out it will become more popular. After parking in front of the gate, the trail commences towards the back left of the field. This would be a good hike for dogs and kids. It is a great option for someone new to hiking - not long nor difficult, but gives a great view at the top! There were many wildflowers once the incline began to even out, and so many more if you follow the service road up a bit from the trail. The service road eventually ends, but you can follow underneath the electric lines up along the ridge (I'm not sure if that's actually allowed or prohibited, though). Eventually, the electric lines connect with the path to the Heybrook Lookout, but there is no official trail nor signs.

We hiked this trail on the Fourth as well. Beautiful day, cooler in the canopy but warm on top. We didn't see anyone until arriving at the viewpoint on the way up, but passed 6-8 groups on our way down (started the hike at 9am). Trail is in great condition, but as previous post notes, the vegetation is a bit thicker at the top. Mileage is pretty accurate, 1.6 to the viewpoint, and marked thoroughly on the route. We hiked a bit further up the old lookout access road before returning back to the base.