Most visitors to Lassen Volcanic National Park overlooks or bypasses the northeastern corner of the Park, which admittedly is an hour's drive eastwards from the northen entrance to the park.   The route includes a 7-mile dirt road which is entirely passable with normal passenger cars at a 15-20mph speed.  Despite the effort it takes to get there, this part of the park gives you a very unique and moonscape experience.  It has the fastastic 4-mile (roundtrip) Cinder Cone Trail, which offers spectacular views of the Cinder Cone, the surrounding lava beds, painted dunes, lakes and remote peaks.  There is also a short (though somewhat steep) trail that goes from the top of the Cinder Cone to its bottom for an even more unique experience.  Getting to the top of the Cinder Cone does require some level of physical fitness.