Dear Robert, the Ultra X-Tremos (http://atitlanreserva.com/wp/en/attractions/zip-lines/) indeed have 7 lines, two of them are more than 870 meters long, lasting more than a minute and half while you get to see one of the most spectacular natura scenarios you could wish for: the giant caldera created by a cataclysmic explosion 83 thousand years ago, lake Atitlan. Many folks find that in itself special, not to mention the adrenaline and sheer contact with nature. Yes the zip lines are 40 euros, 80 for two of you. People often compare this with the 61 euros paid in Antigua and find it a pretty sweet deal. In the butterfly preserve there are usually more than 12 species of butterflies and more than 1200 specimens flying. And as for the spider monkeys, we host seven of them and they can be best seen when fed in the morning or when your bring fruit from the Visitor Center. And I will certainly transmit to our collaborators your very positive evaluation. Thanks for your time and we hope to see you here again in order to give you a more rounded appreciation of what the Reserve offers visitors'. Best Alberto Rivera Manager