Lying between Managua and Granada, Masaya Volcano National Park is a fascinating place to visit, en route between the two cities or as a day trip from either one. The main attraction is the huge Santiago crater which has formed between the Nindiri and Masaya volcanoes. Throughout the 1900s there were frequent eruptions until, in 1985, the craters collapsed; even now sulphurous gasses still bellow forth and you can hear the lava thundering past below ground. Surrounding the national park are some fascinating little market and craft towns worth exploring.