It was a two day trip with a plan to go to Ainodake too. I stayed with me friend at 白根御池小屋 over night. The way to the trail head is easy. I took the bus at Minami Alps Shi Ashiyasukankodai Parking Lot. I was the only one taking the bus (my friend took the same from Kofu). The staff was very friendly and helpful. They made sure I took the right bus. Additionally to the fare, you need to pay 200yen nature perseverance fee. The climb up to the lodge isn't difficult, though it only goes up all the time. The lodge is really nice. Very new and in great shape. Only it's thin walls are annoying at night. Unfortunately in the morning it rained and then snowed heavily. So we gave up going to Ainodake. On the way up we met a few people and they told us the snow is heavy. We still decided to go on as far as we could. Turned out it wasn't so bad after all. The way up to Kitadake isn't that bad as well. Just the deepening snow made it more difficult. I didn't need spikes though. On the top the sky cleared up and gave a brilliant view. Mount Fuji could be seen clearly for short periods. Also we had the second highest mountain all for us alone as there was no one. Before ascending Kitadake we took a short rest at 北岳 肩の小屋 to eat ramen for 1000yen and drink hot corn soup 300yen and hot cocoa 300yen. One thing to note: I payed the bus with pasmo. But on the way back the machine reset and I couldn't pay. So I had to pay with cash. Better bring enough!