The Masaryk Circuit took its name from Tomáš Garrigue Masaryk, the first president of Czechoslovakia, reflecting the national prestige attached to the event. The original layout ran anti-clockwise on approximately 29.194 km of public roads in the outskirts of Brno. The start and finish line was located in Bosonohy. From there the circuit headed east past Kamenny, then turned north past the Bohunice University Campus area near Kejbaly, before threading through the villages of Libusino, Kohoutovice, and Žebětín, out to Ostrovacice, through Veselka, and back via a series of fast straights and kinks to the start. The character of the course was typical of the great pre-war road circuits: long, fast, exposed to ordinary traffic infrastructure and demanding of both machinery and driver.
From 1930 to 1937 the Masaryk Circuit attracted some of the top drivers and factory teams in European motor racing. The Czechoslovakian Grand Prix held there was a blue-riband event drawing the elite of Grand Prix competition at a time when the discipline was dominated by German Silver Arrows and Italian machinery.
After a break during the Second World War, the circuit was revived. On 25 September 1949, a race was held on a shorter 17.800 km clockwise variant of the layout. This event was organised as part of the early Grand Prix motor racing calendar that would evolve into the Formula One World Championship. That single 1949 Czechoslovakian Grand Prix drew a crowd reported in excess of 400,000 spectators, a figure that underscores the event's enormous popular appeal, yet it proved to be the last Grand Prix for cars on the old circuit configuration.
Beginning in 1950, the old road circuit shifted its primary focus to motorcycle racing, hosting the Czechoslovakian Motorcycle Grand Prix. The event became a round of the FIM Motorcycle World Championship from 1965 onwards. Each decade brought further reductions in circuit length. By 1964 the course had been trimmed to 13.941 km by completely bypassing Žebětín and incorporating a new through-road to Kohoutovice. A further reduction in 1975 brought the length down to 10.921 km; this version exited Kohoutovice from the south, bypassed Libusino and Kejbaly, and cut through Kamenny to rejoin the main road back to Bosonohy. The European Touring Car series visited the circuit in the 1980s while it was still in this shortened form.
Despite being a street circuit subject to decades of shortening and rerouting, the old Brno road layout remained competitive at the international level well into the 1980s. As of the mid-2020s, all public roads that formed part of the various iterations of the old circuit still exist, offering a tangible connection to the era when European motor racing routinely used ordinary highways as its venue. The circuit's history fed directly into the case for Brno receiving a permanent purpose-built facility, which opened in 1987 and allowed the Czech Republic's motorsport heritage to continue under modern safety conditions.