The Impossible is the only national park in El Salvador. It is southwest of this country that is smaller than Caceres. But distances are measured differently in Central America! If you travel from the capital, San Salvador, it will take you about a day to get to the park, although they are less than 100 kilometer away. Communication is very bad and there aren´t many options, especially in the last part of the trip. But when you get to the park it will be worth it. This book is the only one that preserves the native forest of El Salvador. The facilities are well maintained and there is free camping -although you have to pay the park entrance.