Now, this is serious stuff. Only 37 kms from Saint Pierre, but with 400 curves... very, very thightly bound! It's better to start the trip early, 6am is fine, as the clouds take over Cilaos as soon as eleven am. Better to pick a dry day with no major rainfall on the previous days, as the cliffs are very fragile and end up on the road very often after big storms. The views are spectacular. The road is in good condition, but there are two tunnels to pass through, with no light inside and with room for just one vehicle to pass at a time. The ride is fun, but in some tight curves there is no visibility, better use the horn! Cilaos is very pleasant and worth a longer stay, if you get caught by the clouds before coming back down to Saint Pierre! If you're in luck and the sun holds, go to Ilet à Cordes by the D242. It starts on the heights of Cilaos. The D242 is a very narrow road with crazy bends, but with many places to take great pictures from! A rarity in La Réunion. But again: don't get caught by the rain up there. It's hell, very fast!