Such a beautiful machine.
The Carrera 6, more commonly known as 906, is not only astonishingly beautiful, but indeed one of the most important cars in Porsche's racing history. See, as gorgeous as the 904 looked, with its ladder-frame chassis it was a technological dead end. Part of its torsional stiffness, for example, relied on the heavyish layers of fibreglass that enveloped the actual steel structure: fine for a small sportscar/GT, not so much for a true racer.
With the Carrera 6 things were approached differently, with a proper spaceframe and paper-thin bodywork - the outer shape itself being researched in a wind tunnel. Heady stuff in the mid-sixties for a small outfit as Porsche was then.
There were compromises: suspension arms were carried over from the 904 (although I understand the uprights may have been different?), and the wheels were huge 15 inchers when even in F1 they had already transitioned to 13". Maybe the reason was just parts-bin raiding to keep costs in check - or maybe Porsche still fancied fielding a racing car that technically could be driven on the road (although not in Vaterland, of course). Driving on the road the Carrera 6 duly did, anyway, entering a few rallies and, of course, the Targa Florio.
Even the engine was a little special. Based on the 2.0 911 six, it had quite a few interesting parts (titanium rods, twin-plug ignition, for example), with a max power output of 210 bhp. Later the same spec was used in the legendary 911 R and the 914/6 GT (also known internally as 914/6 R).
Arguably Porsche big-league dreams (and results) started with the Carrera 6. Up to perhaps the 962, all their pure racers that followed (i.e., 911 derivatives excepted) can trace their lineage to that spaceframe and early aero efforts.
The beginnings of the Carrera 6s also involve a works hillclimbing special, the 906 Bergspyder (see?), which, simplifying a lot, could be considered the missing link between the 904 and the Typ 906 as we know it. Very interestingly that first spaceframe chassis repurposed some Lotus parts (uprights and hubs, IIRC). Perhaps for the first time in Porsche history someone was paying real attention to unsprung mass.
Guess who was the driving force behind the car, a young engineer ready and willing (or rather anxious) to make his mark in the motoring world, let alone the company? His name may sound familiar to you: Ferdinand Karl Piëch.
About that lovely picture: I immediately thought "Nürburgring, maybe Flugplatz" and "Leo Kinnunen". According to the Net, it is indeed Nürburgring (and, due to the "yump" it could well be Flugplatz), in the year of the Lord of 1969, but the gent was another Finn: Hans Laine, teaming with a Swede, Sten Axelsson, and yet another Finn who did not drove, Antti Aarnio-Wihuri. The year before the same car had been raced in the same event by Aarnio-Wihuri and Pauli Toivonen, no less (father of Henri and Harri and a legend in his own right).
That car, s/n 906-125, has survived and is owned by Miles Collier: https://www.collierautomedia.com/1966-porsche-carrera-6-case-study-in-archaeological-restoration
Side note: many moons ago I met a car enthusiast who used to own, or maybe still owns, one of these. A true time-capsule-style barn-find, only in this case the "barn" was a basement in a small village. I don't know all the details, but I remember being told that the first floor of the same building housed the local office of an extremely radical political party notorious for direct, violent street action. Removing the tiny racer from its resting place entailed careful planning so as not to attract undue attention.