Makushin Valcano is the highest point on the island of Unalaska, located in the Aleutian Chain. The upper areas of the peak are glaciated and ice covered. Makushins is an active valcano and last erupted in 1995. On a clear day you can see the fumaroles smoking on the summits 2.5km wide caldera. I read somewhere that during WWII, the 10th Mountain Division had to climb Makushin as part of their training. Even though the elevation is only 2000m, the remoteness of the peak and the extreme weather that frequents the Aleutians makes the climb much more then a hike up.
This part get's a little tricky... Dutch Harbor is the name of the City on Unalska where you fly into. PenAir is the only air line that services the island, and they aren't cheap. Once you get to Dutch Harbor, Makushin sits about 24km west of Dutch Harbor, but I don't recommend starting out from the city. It is much easier if you can jump on a boat and get dropped of a little closer.
The land is owned by a native corporation that request people by land use permits. However the don't actively enforce it, and there isn't going to be anyone remotely close to you on Makushin to give you a hard time.
For longer days and milder weather I would say June-September. The only problem with the summer months is the vegetation lower on the mountain is a pain to travel through. The earlier in the summer you start the less vegetation there will be. If you do a winter ascent you can ski the whole way up it.
No huts, but camping is everywhere. Finding a dry spot to camp is a little harder.
Once you are in Dutch Harbor the best chance of a forecast you have is looking out the window. Other then that I recommend checking the Alaska Volcano Observatory website, they have some good info on the mountain, and that way you might have a better idea of it's going to erupt while you're on it. Also up on the mountain there aren't any running streams so all water has to be boiled down from snow or collected from melt and rain puddles.