Methods, computer program products, and systems are presented. The methods include, for instance: providing a cognitive tour guide service to a group of participants for a tour with an initial route planned by participants registration information and environment information along the initial route. During the tour, real time sensory data on the participants health characteristics, change in environment are collected by a cognitive agent accompanying the group to lead the tour are relayed to a cognitive tour guide engine, and real time multi-objective optimization is modeled and performed. The participants are regrouped responsive to their respective enjoyment and circumstances of the environment and, among a set of optimal solutions, a new route for the tour is selected based on participant preference modeled and trained by participant feedback. During the tour, the cognitive tour guide engine continuously optimizes route responsive to incoming real time sensory data.