We spent Friday night at anchor then on Saturday went through the Corinth Canal - what an experience. Very unusual system where the road bridges sink down 6m below the surface of the water to allow boats to sail through! We had to wait for 2 other boats to arrive before we were allowed through. Unfortunately they were both large motor yachts which went at top speed and the canal office kept radioing us to tell us to speed up and not fall behind the others but we were already at close to top speed (under engine of course) and I don't like to push the engine at absolutely full revs. So we fell behind a bit and then the office was on the radio again telling us i thought to increase speed - when I acknowledged message it transpired the office now wanted us to decrease speed!! (either his english, the radio transmission or my hearing wasn't clear). They'd decided to take the opportunity of the gap between us and the two boats ahead to raise the road bridge and allow traffic across before lowering again for us! So we slowed to minimum speed while still keeping steerage way (the canal is only 25m wide so not much room for manoeuvre!) and then the office was back on the radio saying "ALMA FULL SPEED FULL SPEED" and they started to lower the bridge again - although it wasn't clear that it would be fully lowered by the time we arrived if we went at full speed so we compromised on the speed and then just to cause a bit more concern we noticed the signal lights for boats were still red! Back on the radio to the office to query the red lights. "ALMA FULL SPEED, FULL SPEED" and just as we got to the bridge the lights changed to green, we went through (over) and out into the gulf of Corinth with great relief. Quite a lot of stress but great experience.