Hi, have to admit that I generally prefer hotels that attract mainly adults too. After a good many years as a youthworker and now teaching undergrad students I do prefer, shall we say, more mature companions
I see you've been tempted to book to go back earlier than planned? f you do get the chance while over in Varadero, the Vinales area is well worth the effort. An amazing landscape with rock features call Mogotes which are like giant Tunnocks tea cakes rising almost straight up from flat plains! In local slang they are compared to a certain part of the female anatomy
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There are also some very interesting cave systems at that end of the island. Pinar del Rio is worth a look too - a very lush landscape - as is Las Terazzas which is up in the hills. Enjoy
SM