I think I have touched before, but I think it would be good to touch in with more depth.
the AoS' location, in-game, the clues I am given is:
- It is set in 'Hakuba Shrine' in Japan.
- The 2035 Total Solar Eclipse passes the area, while showing the max size of the eclipse
- The weather around the area is just a little bit cold that people wear trench coats, but the leaves are still green in early September.
The DoS' location, in-game, the clues I am given is:
- It's still set in Japan.
- It's in a big lake (it's not a oceanic location. The area is covered with spruce-looking trees)
- There are two landmasses in middle of the lake, big enough to support a Gothic castle and a tower each
I think the location for AoS; the location of Hakuba Shrine is this shrine in Hakuba-cho, Nagano prefecture.
https://www.google.com.au/maps/place/Sokomiya+Hosonosuwa+Shrine/@36.6996958,137.8436032,9188m/data=!3m1!1e3!4m5!3m4!1s0x5ff7ce0868e49719:0x6127f83ff68937b!8m2!3d36.701714!4d137.8403427According to Wikipedia
https://en.wikipedia.org/wiki/Hakuba,_Nagano, in September, the average temperature for Hakuba is Max. 23.4C, Min. 14.2C. Not that cold, but a reasonable weather to wear trench coats.
About the shrine itself, it is located in a bushy hill, which allows people to overlook the eclipse after walking on a stairway surrounded by trees. Also, it is a little local shrine, and there is better place for eclipse watching; a ski resort used for 1998 Winter Olympics, so it explains that there is only few people around at the time of eclipse.
The eclipse
https://eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2035Sep02Tgoogle.html?zoom=1 (sorry for inconvenience, btw), passes the region with 100% obscuration and 1.007 magnitude. In another word, the eclipse can be seen
very clearly around the region at the eclipse of Spetember 2nd, 2035.
DoS' location, I think is Lake Towada, located in Akita pref. and Aomori pref. it is a big lake, with two peninsula. One big peninsula with circular edge, and a small peninsula. The big peninsula will be the main castle and the small peninsula will be the tower. Nearby is a rural town. It would be the town area in-game.
https://www.google.com.au/maps/@40.4563321,140.8762678,13887m/data=!3m1!1e3 The lake is cited in rural area, perfect for a cult base. Also, according to wikipedia,
In 1953, in order to popularize the lake and the park, a sculpture of two women titled “The Maiden Statue” by Kōtarō Takamura was dedicated at the lakeshore as part of the park's 15th anniversary celebration. It was the last work by that noted sculptor.
Maybe this has to do with the plot. Notice 'a sculpture of two women'. How many female characters 'died' in the plot? (I'm putting apostrophe for a purpose)
The temperature
http://www.accuweather.com/en/jp/towada-shi/216885/month/216885?monyr=9/01/2017, in September, ranges from 26C to 9C (althouch being 2017 estimation). Although not being that cold, it is considerably cold to wear winter clothing. About the snow, maybe Celia used a spell to make the area cold, thus the area is covered in snow since the precipitation of the area is quite high.