Deep Blue Sea

This Swiss climber's blog post is fairly good for the route.

https://verticalsoul.blogspot.com/2016/11/eiger-deep-blue-sea.html

A famous free climb route on the Eiger north face that was made known in the US by Dean Potter's FreeBASE ascent.

Approach via abseil/down-climbing fixed ropes (if they are in place) in the vicinity of the exit of the 1982 Brunner-Ochsner route (marked by a big cairn) and then move east along ledges (including section of fixed rope) to start.

The rock is mostly very good, considering it is the Eiger. Bolts can be far apart but the small rack makes it manageable. IMO if you are a solid onsight climber at 5.12 (on limestone) and have a good lead head it is a fun adventure! Otherwise it can be a dreadful experience. Have a day out on the spectacular Wendenstocke to test out your partnership if you have doubts. ;)

Obligatory climbing is around 7a/+, although that can feel exposed/scary in bad conditions or if that's your onsight limit.

Here is a pitch breakdown for those who are interested:

P1 - 11a 40m

The route starts at the red painted "DBS", and goes slightly right to the first bolt and then straight up for 35m to the first belay on a good ledge. Amazing slab climbing on edges and huecos in dark grey rock. 6 bolts and a .5 (purple totem).

P2 - 11a 35m

Head right and up slightly broken rock to the first bolt, then up through steep blocky terrain passing some holes (can place pro here) to another bolt. Clip this, and make a rising traverse to the left to the belay. 4 bolts.

P3 - 11d 35m

Climb up to the obvious roof and make exposed moves to clip the first bolt. Boulder through the roof on mostly good holds to a good stance. Clip another bolt and head straight up on perfect edges to a tricky sequence through a few pockets where the angle steepens. Once through the crux go left and up on amazing slots to the belay. 6 bolts.

P4 - 12c 30m

This pitch is all about power endurance, pumpy with few great rests. Head straight left off the belay and into three bolts of technical and slightly bouldery sidepulls. Get a good shake and climb up and left through small edges into a small dihedral where you can place a .75 (green totem). Awesome steep climbing on perfect rock. 7 bolts.

P5 - 12a 45m

Another amazing pitch, long and sustained. Head straight up and slightly right through more amazing edges, slots and jugs. Look for gear in horizontals to supplement the bolts. Reach a ledge and get ready for the exposed and heroic traverse out the roof to the right and across the face with an improbably sequence on amazing rock. After this crux climb up the the ledge above and belay. 7 bolts. 

P6 - 12a 35m

From the belay head left along the ledge until it ends (you can't see the first bolt until you are right next to it). Things get steep again as you head through the roof and onto the thin face above. Move left to better holds and another bolt. Keep traversing up and left (gear can be had in horizontals) through wildly exposed terrain to a large horn and another bolt. More leftward traversing takes you to the final boulder to the ledge and the belay. Epic. 5 bolts.

P7 - 11d 45m

Traverse slightly down and directly right from the belay for about 30 feet, clipping a two bolts along the way. From the second bolts climb up into a small corner, and then make tricky moves to gain a dihedral. Get a good rest here because things get steep and pumpy for a long way until you reach a ledge and the belay. Pumpy and sustained. 7 bolts.

P8 - 12c 40m

The final crux! Head up and left on slopey rails, clip the first bolt, and make tough moves on sidepulls to clip the second bolt. Execute a sequential boulder problem, clip the third bolt, and traverse hard right to a chossy corner. Clip another bolt and clip up the corner (careful of loose rock!) until you reach another bolt on the face to the right. Move right onto the face and through easier edges to the belay. 6 bolts.

P9 - .8 25m

Climb a easy corner and head straight up through chossy ledges to the summer anchors. Be very careful not to drop rocks on your belayer! 1 bolt, #2 Camalot.

Every pitch on this route is amazing and steep. If you are going to do one wall in Switzerland, this should be it. An amazing journey and one of the best routes on such an iconic mountain. As stated above, be prepared to climb well above your gear!