Azerbaijan was the last of the three countries in Caucasus that we visited. Having traveled to the other two (Georgia and Armenia), the expectations were set quite high as the neighbors were simply amazing.
Full of natural gas, Azerbaijan is the richest country in the region - its capital, Baku, is being renovated and an extremely modern center is built next to the charming old town which looks as if taken out of a southern European country. The food is unbelievable and so cheap - for 15 EUR, you can enjoy the best quality ever meal in a local, high class restaurant. Baku (just like Tbilisi or Yerevan) should be a new destination for a weekend break - especially that cheap airlines fly there from Europe.
Azerbaijan is pretty small so a few days is enough to be able visit quite a lot. Apart from Baku, you can find some unique attractions in this country, such as mud volcanoes, ever burning ground (tiny version of the Door to Hell crater), ancient wall paintings and the village of Khinalug located deep in the Caucasus mountains.