Renaissance: How Europe reconnected to its Antiquity heritage?

Middle ages, called also �Dark Ages� saw total loss of continuity between Greek and Roman Antique cultures and medieval Europe. Renaissance started when Europeans rediscovered writings of Ancient Greeks and Romans. This restarted art, science and technology after thousand years of darkness. Empirical methods were brought back to Europe. Who was custodian of all that knowledge during Dark Ages and how we got this knowledge back?

If you chose "Other",  could you provide some explanation for your choice?

I disagree with that view. The renaissance began in Italy due to diverse factors. The reconquista originated a completely different mentality.

But they weren't stupid. Have you ever heard an architect speak of the gothic cathedrals. You'll get the impression that only aliens could have made them.

No it didn't. The renaissance we know spread from Italy. 

Actually, as I understand it, Mystra was quite a place of learning 

I've stated once before that I find the arab contribution to the renaissance to be a bit overrated. It was very passive, after all. Monks had to go there and get the information they needed. Not only that, but monasteries were intellectually active places, whether you like it or not. And Byzantium did conserve a lot. The Crusades hardly contributed to the intellectual improvement of Europeans.

The XV th century renaissance is a purely Italian thing, that can only be explained taking into account Italian history and culture.

The twelfth century renaissance is considered by some to be far more interesting. And it is mostly due to the improvement of a monk's education, and perhaps to the decline of arab power (as some say)

 You are joking aren't you. You think gothic cathedral were simple? You  probably don't have a clue about what you are ranting about. Gothic cathedral such Amien is as complex as it can and structures of such complexities is not seen anywhere else. trial and error was reasonable in the early age, once the technology was mastered, gothic architecture rich it peak in world architecture. Modern architecture will all it's engineering is not that complex. Gothic architecture is htouroughly studied in most western school and it still  influence modern architecture which is usually simpler despite the use of more advance engineering.

 Tell the arabs either build anything like Amien or the cathedral of cologne.

That old-fashioned wiew of the middle ages is utterly false and is strongly opposed by most modern historians. The "Dark ages" were not dark, it was a time of development, european integrity and expansion. The antique herritage was not preserved no I admit that - but it was developed! When the renaissance people "rediscovered" the classics they merely made a step back in history, ignoring the development during the previous centuries...