Standing on the small saddle, the south summit is protected by about 15 feet of a near-vertical rock band. There's a shoulder width 5th class chimney with good hand and foot holds that you can squeeze through to reach the top of the rock band. Exciting moves here! From there it's a 3rd-4th class scramble to the 6-8 butt flat summit. Approach the summit directly from the west for the most challenging 4th class scrambling. The exposure looking off this summit block is impressive. Getting down is the hard part - even though I've down climbed the chimney on prior trips, I was not comfortable down climbing the steep chimney without a cordellette or short section of rope slung over some natural pro as a safety line to hold onto for protection from falling backward. You could easily rappel the chimney with a rope and harness. Alternatively, if you leave the summit off the more gentle sloped rock on the east side, you can work your way down through a series of 3rd-4th class ledges until you intersect the couloir about at the midpoint. Then you can scramble back up to the saddle. Getting down through the ledges and zig zagging back to the couloir is tricky with exposure and, depending on the climber, a rope may be wise if not just for a hasty-arm rappel, then with a top anchor and rappel with a harness. A short section of rope is probably wise for this climb even if all the climbers are experienced and comfortable with exposure - if you had rain or grauppel while you were on the rock, using a short length of rope could avoid an accident on slippery rock. Helmets are probably optional since the chance of rockfall from above is minimal provided a group stays close together in the couloir. But, a helmet is great insurance for just banging your head on rock when climbing.
From the saddle, the 3rd-4th class scramble up to the north summit is easier with no rock bands to negotiate. You will arrive at a very airy small flat area in the rock about 6 feet below the 1 butt summit block. This is the smallest peak I've seen on any Colorado summit (much smaller than Sunlight but without the "step across oblivion" move) and there is a small depression for 1 butt on the very top. Check for the bird droppings before seating yourself! You can boost yourself up onto the tiny summit and look down the intimidating east face of the Citadel. As an alternative to down climbing the steep, slippery couloir, descend NW from the north summit - you will see obvious climbers' trails leading down through less steep scree and talus. Work your way down to the bottom of the Citadel rock face and you will be about 50 yards past the couloir that you ascended. Traverse back around the rock face and reconnect with the ridgeline trail.
I checked the top elevation of summit, and they read identical with my Suunto X-6. A few years ago, when checking them with a GPS, the north summit read slightly higher. Guess they are truly twin summits. Whatever - this is a great climb and the rugged rock resembles the Crestones. GPS measured 3.2 miles from the TH to the summit. The vertical gain by topo from TH to summit is 3,000 feet; my Suunto recorded 3,200' on the ascent and 3,500' on the descent. The Citadel protects some great climbing on the challenging twin summits.