Back in the ’90s, Alfa Romeo dominated touring-car racing. The 155 won the DTM championship in Germany, the Superturismo in Italy, and both the Spanish and British Touring Car Championships. So the Italian automaker planned to celebrate by producing a Stradale version to challenge the likes of the BMW M3 and Mercedes 190E 2.5-16 on the road much as it had on the track.

Unfortunately the project was aborted, but there was one prototype built. And now it’s coming up for auction, offering one lucky buyer the rare opportunity to take home a truly unique set of wheels.

Designed by the legendary Abarth engineer Sergio Limone, father of the Lancia 037, the 155 GTA Stradale was based on the 155 Q4 but shared more with the Lancia Delta Integrale. Its engine was prepared to Group N competition specifications, and the body fitted with a more aggressive-looking aero kit. The suspension was upgraded too, as was the interior.

Unfortunately cost considerations, and the Fiat board’s disappointment that it couldn’t accommodate a more powerful V6m led to the demise of what could have been the precursor of today’s Giulia Quadrifoglio. After the concept’s debut at the Bologna Motor Show, it was briefly used as the medical car during the 1994 Italian Grand Prix at Monza. But then it went into storage, trading hands a few times over the years since.

Long since restored to condition befitting its rarity, the one and only 1993 Alfa Romeo 155 GTA Stradale concept car is now heading to the auction block, where it’s anticipated to fetch some €200k (or about $230k in equivalent US funds). Bonhams will sell it off to the highest bidder later this month at its sale in Padua, Italy, just outside of Venice, and a couple of hours to the east from Milan where Alfa Romeo was founded over a century ago.