The Avenc Ample is the widest of the three potholes (25 m) and is 60m deep. In 2001 a group of potholers from Gandia found a side chamber which contained wonderful stalactites and stalagmites, crystalline pools of water and completely smooth floors which look like ice. Click here for a great picture. There are other pictures on the Federacio d'Espelologia de la Comunitat Valenciana website (link opens in new browser window).
The sign next to the hole explains that it is the habitat of rare and threatened species of flora which have lived there since the last ice age. These plants are typical of the Atlantic climate and survive in the pothole thanks to the microclimate created by the cavity.