The Lebanese Space Program started in 1960 as a hobby club formed at Haigazian College and appropriately called the Haigazian College Rocket Society.

The rockets they built were considered to be "sounding rockets" - that is, the rockets were small, had no payload capacity, and never had a chance of reaching orbit.

The claim that they were the third most advanced space program seems to stem from the fact that in 1962 their third named rocket managed to make it above the 100 km line that is usually used to separate the Earth's atmosphere from space - but again, the rocket never came close to actually reaching orbit.

That rocket, named Cedar III, weighed slightly over 1 ton. For reference, the Juno rocket that put America's first satellite into space in 1958 weighed about 32 tons.

Although the club was founded by students it manufactured its rockets at a Lebanese military factory and received substantial funding from the military. In 1966 the club's original faculty adviser and the source of its initial designs, Manoug Manougian, left the country to take a teaching position in the US, though by that point the club had been completely taken over by the military.

Israel became concerned about the program's militarization, which caused them to pressure France to pressure Lebanon. During the Six Day War, Charles de Galle made an unspecified threat to Charles Helou, then President of Lebanon, and the program was shut down shortly thereafter.

But was this program still the third most advanced rocket program in the world in 1962? The simple answer is no. Every major country with a military rocket program - including the US, Soviet Union, UK, and France - had launched rockets above the 100 km limit by the early 1950s. The German V-2, was even capable of doing that by 1944. And unlike the Lebanese Cedar rockets, those early military rockets were designed to carry a payload other than the rocket itself.

In fact, Lebanon's program wasn't even the most advanced rocket program in the Middle East - that goes to Egypt which began its own program in 1957 with help from West Germany. This program resulted in the creation of two different short range ballistic missiles by 1962 - the longest range of which could fly about 650 km. Either of those missiles could have easily breached the 100 km vertical limit had they been pointed straight up as the Lebanese Cedar rockets were. And again - these were full fledged payload carrying rockets, not the small sounding rockets that Lebanon was producing.

Really, the only claim to fame that the Lebanese program has is that although it eventually turned into a military run program, it began as a purely civilian endeavor and none of the rockets that it produced had an overtly military nature.

But were the rockets somehow advanced or special? No, they were relatively simple sounding rockets and never did anything that would be of note but for the fact that Lebanon was a small, poor country.

Source:

Jörg Determann. Space Science and the Arab World

I'd be interested to know whether, and to what extent, it would have been subsumed into French aerospace programs (and eventually the European Space Agency) and continued there.