Here we have the Open U.P. (Unbeaten Path)
which was released in the summer of 2015 so there are quite a few out on the trails already, and might be correctly called a trailblazing model in this category. If there are similar bikes that predate the U.P. please correct me.
U.P. (Unbeaten Path) combines a performance-oriented cross/road geometry & parts with clearance for mountain bike tires. So you can ride anywhere, and ride fast. Get out of town on asphalt, hit the gravel roads or switch to singletrack. The geometry gets you there fast; the big tires make you unstoppable.
The website says it can fit 650b mountain bike wheels with tires up to 2.1" wide, or 700c wheels with cross tires up to 40mm, or anything other combo that has a total radius of about 340-350mm and allows 6mm clearance between tire and frame.
It features a full carbon frame and fork, and fully internal cables and hoses which may or may not be a feature depending on your personal preferences. Premium product for a premium price, available as a frameset for $2,900 USD
Frame: OPEN U.P.
Frame sizes: S, M, L, XL
Frame weight: 1150g (size L)
Fork: 3T Luteus II Team with 15mm thru axle (included)
BB std: BB386EVO
Chainring fit: Max inner ring: 36t
Max outer ring: 50t (more is overkill with the bigger tires)
Max single ring: 50t (flat rings, best cassette alignment)
Max single ring: 46t (SRAM 1x offset ring, GXP axle)
Max single ring: 44t (SRAM 1x offset ring, 30mm axle)
Headset std: Integrated Tapered IS42/28.6 | IS52/40
Seatpost Ø: 27.2mm
Rear axle std: 142x12mm thru axle
Rear brake std: Post mount for 160mm disc
Cable routing: Internal via exchangeable MultiStops for 1x10/11, 2x10/11, Di2
Bag mount: 100mm front-post-to-bearing-bore-edge
Incl. in box: Frame, fork, headset, seat collar, front thru-axle, spare rear hanger