Niwot Ridge is right in the heart of the Indian Peaks. It's not very prominent, and most of the traffic it sees is heading elsewhere. Hell, being on the south half of the ridge is technically illegal. Apparently, my footprints ruin Boulder's water.
Most of the ridge is fairly long, gentle, and spacious. There's the remnants of some service road, and plenty of weather/atmospheric monitoring goodies. It's a good tundra stroll for pretty much anybody.
After the weather station is where things change. The whole ridge narrows to a knife edge that tops out just a hair above 13,000 feet in what seems like no time at all. There's also a nice view of the Isabelle Cirque, Navajo and Apache Peaks, and of course the looming face of Kiowa.
The knife edged section offers anything up to some rather edgy 4th class, depending on which route you take. Expect plenty of solitude, despite how busy the Brainerd Lake area can be, and some amount of adventure.
The easiest way to access the ridge is through the Brainerd Lake Recreation Area. There's a trail that branches off the Jean Lunning Trail that's supposed to take you to the top, but I never found it. If you can't find the trail, don't worry. You can just go straight up the side. The whole ridge runs along the valley. It's probably better to go up sooner rather than later, as the further the ridge goes, the steeper the sides get.
There is also another way to access the ridge a bit further south on Highway 72, but I've never tried it and have no idea where it puts you. I believe it's called the Sourdough Trailhead.
If you go in through the Brainerd Lake Recreation Area, you'll have to pay the entrance fee. I swear it changes every year. Just to be safe, expect to pay 10-12 dollars to enter the area. Also, apparently the south edge of the ridge is in the Boulder Watershed. That means, if they catch you trespassing, prepare to pay a rather large fine.
If you wanted to fight a million people for a spot, I GUESS you could attempt to camp at Brainerd Lake. Otherwise, it's more of a day trip area.