A group of environmentalists went on hiking in the mountains of Calbayog City. They hiked to see the tourist's spots there and to check if the tourists have been responsible in taking care of nature. After walking a distance of 3 km, they rested and had their lunch at Tabokno Falls. Then, they hiked for 2 km more. In returning home, a resident in the place showed them a shorter way which was 3 km only. How many kilometers did they hike in all? ​