We hired a car and drive to the volcano through wonderful scenery and the volcano crater was spectacular. The plumes of smoke can be seen for miles but to stare into the deep crater is amazing. Fantastic views however a lot of trails were closed for safety. Well worth a visit and the small but informative museum and information centre was really great. A must if you're in Nicaragua. It is located just off route 4, which is a good road, and only 30/35 km from Managua.