The hike up to the active crater of Pacaya Summit at over 8,000 feet high will take you about 3-4 hours roundtrip if you walk all the way from the bottom. You can take a jeep halfway if you are limited on time. The hike is super steep and on uneven lava rocks for the last 45 minutes, but the views at the top into the crater of the active volcano are amazing! You can see the three other volcanoes in the distance and hear the "breathing" of the volcano as it steams.