Mt. Myojin (明神山, Myojinyama) is one of the best spots to see Mt. Fuji. You can reach the top with Panoramadai/Sangokuyama Hiking course. You can also see great view of Lake Yamanaka. Panoramadai Hiking course is very open space but it has a sharp inclination.
If you are not hiker, but you want to see the best view of Mt. Fuji. Drive up to Sangokutoge. There is parking for hikers. It will be only 30 min. hiking. However, the grade is even higher.
0. at Kawaguchiko Station.
1. use Fujikyu Line to Fujiyoshida (5 min.)
2. use local bus to Sangokuyama Iriguchi (1 hr. 30 min.)
3. walk along the panorama/sangokuyama Hiking course (35 min.)