The simplicity of this rose makes me think that it’s close to a species rose, but nobody knows for sure. It’s classed as a gallica, maybe for lack of better information. While most near-species roses are nicest grown as a free standing shrub, I think you’ll find it rewarding to give ‘Complicata’ something to climb. You’ll find nicer pictures out there, but here’s one I snapped in the garden (aphids and all!):

The blooms are dark pink at the edges, white nearer the center, with prominent yellow stamens. What you can’t see here is how large they are! The only other single I know to compete on bloom size is ‘Altissimo‘. The large size of the flowers, their simple form, wonderful scent, and the fact that it blooms in one main flush of flowers makes this a stunning shrub (or better, a climber) in early Summer.

‘Complicata’ can grow to 10 feet with some support, or to a lax shrub of 6 feet or so. It also sets hips after blooming, for fall/winter interest.