León is about 90 kilometres northwest of Managua, connected by a good two-lane highway. Express buses and ordinary buses run frequently from the Mercado Israel Lewites (also known as Mercado Boer) in Managua and take between 1.5 and 2 hours. Chicken buses are cheaper and slower; express minibuses are faster and barely more expensive.
From Granada or Masaya, you need to connect through Managua — there is no direct service. From the northern highlands (Estelí, Matagalpa), there are direct buses. León also has a small airstrip but no scheduled commercial service at the time of writing.
The bus terminal in León is a few blocks from the central park. Taxis and mototaxis meet buses and will take you to any accommodation in the centre for a negligible fare.