Complex sentence: There were a total of fourteen stages that contained categorized climbs, of which four had summit finishes: stage 6 to Campitello Matese, stage 12 to Selvino, stage 13 to Chiesa in Valmalenco, and stage 15 to Merano 2000.
Split into simpler sentences: There were a total of fourteen stages that contained categorized climbs. Of the stages containing categorized climbs, four ended with summit finishes: stage 6 to Campitello Matese, stage 12 to Selvino, stage 13 to Chiesa in Valmalenco, and stage 15 to Merano 2000.