Motor racing had been staged near Tripoli as early as 1925, initially on improvised circuits outside the city. Those early events were promoted as a tool to raise capital and attract settlers to the Italian colony of Tripolitania, under the encouragement of the colony's governor General Emilio de Bono. Financial difficulties plagued the series: only personal intervention by de Bono saved the 1929 race from cancellation, and the 1930 edition was marred by a sparse field and the fatal accident of Gastone Brilli-Peri. A 1931 race proved impossible to organise, and the future of the Tripoli Grand Prix was in doubt.
The event was rescued by Egidio Sforzini, president of Tripoli's automobile club, who secured government funding tied to a colonial trade fair and used the capital to build a permanent European-standard circuit. The new Mellaha Lake track was completed in time for the 1933 season.
The Mellaha Lake Circuit measured 13.140 kilometres (8.165 miles) and ran through flat terrain in a salt basin situated between Tripoli, the suburb of Suq al-Jumaah, and Tajura, looping around the perimeter of Mellaha Air Base. Its most recognisable landmark was a tall white concrete tower positioned opposite a large frontstretch grandstand capable of holding up to ten thousand spectators. The facility included electronic starting lights — an innovation at the time — and amenities comparable to the leading continental circuits. The long, fast layout and wide open desert setting allowed exceptionally high speeds.
Racing driver Dick Seaman famously described Mellaha Lake as the "Ascot of motor racing circuits," and with its substantial prize fund it became one of the most sought-after dates on the European Grand Prix calendar.
From 1933 to 1938 the Tripoli Grand Prix ran to Formula Libre regulations, placing no restrictions on engine size or weight. This produced an environment dominated by the fastest machinery in the world. From 1935 onwards the German Silver Arrows — Mercedes-Benz and Auto Union — controlled proceedings. Hermann Lang won three consecutive runnings in different machinery: the W125 in 1937, the W154 in 1938, and the W165 in 1939.
The 1933 inaugural Mellaha running was attended by accusations of race fixing. The event was run in conjunction with a state lottery under which 30 tickets were issued before the race, each matched to a driver; the ticket-holder whose driver won received three million lire. Alfred Neubauer's 1958 memoir Speed Was My Life claimed that Tazio Nuvolari, Achille Varzi, and Baconin Borzacchini conspired to split the lottery winnings by agreeing on a pre-arranged result. Later research has concluded that this story is almost certainly a myth invented by Neubauer, who was not present at the event.
In 1938 new Grand Prix regulations capped engine displacement at three litres supercharged; the Mercedes-Benz W154, though smaller than its predecessor, still produced over 450 horsepower and maintained German dominance.
For 1939 the Italian organisers, frustrated by years of German victories, restricted the race to Voiturette regulations for 1500cc supercharged cars. The Alfa Romeo 158 Alfetta and Maserati 4CL were the primary contenders. Mercedes nonetheless entered two specially developed W165 cars and won through Lang again, defeating the field on its first competitive outing.
The final race was held on 12 May 1940, with Italy still nominally neutral as the Battle of France began. Only factory Alfa Romeo and Maserati entries competed in an all-Italian field of 23 cars. Giuseppe Farina was quickest in practice and took his only major pre-war victory. With Italy's entry into the Second World War weeks later and the subsequent fighting in North Africa, the Tripoli Grand Prix was never held again.
Mellaha Lake Circuit stood as a symbol of the Italian colonial project in Libya and of the pre-war Grand Prix era's appetite for spectacle and speed. The circuit's combination of fast open straights, substantial prize money, and luxury hospitality — competitors were housed at the Hotel Uaddan with its casino and dinner theatre, and were entertained by Governor-General Italo Balbo — gave it a glamour that few events of the period could match. The lottery mechanism, unique among Grand Prix of the era, added an element of commercial theatre that drew enormous crowds and national attention.
The circuit's site today encompasses what is now Mitiga International Airport.