need to go early: the buses from train station to ヤビツ峠 run only early
trip: let google maps plan your trip for going to ヤビツ峠, 神奈川県. Probably involves train to 秦野駅 and a bus.
then: ヤビツ峠 →(1h04m)→二ノ塔→(15m)→三ノ塔→(1h17m)→新大日→(40m)→塔ノ岳→(2h16min)→大倉バス停. From there take the bus to 渋沢駅/Shibuzawaeki, from there back to Tokyo.
Android app 'osmand' knows these locations and pathes in between
Station 鶴巻温泉 is 3 stations far away into direction Tokyo. It has an Onsen near the train station. Not great, but ok.
In mid of August (I went 2018), plants have grown over the way at many places. If you are worried about bugs, wear long trousers and a shirt with long sleeves.
In February (I went 2019), there might be snow. The bus is not running until ヤビツ峠 then. Bus line 20 runs just until 蓑毛/Minoge bus stop, one can walk in ~70min to ヤビツ峠. If you do this trip while there is snow, you should bring アイゼン/Eisen with you, so spikes for the shows. I did the trip without アイゼン or sticks, and strongly recommend to not do this.
a 3.5-5.5 hour trip from Okutama via Honnitasan to Hatonosu station
West of Tokyo
take train to Takaosanguchi(高尾山口), 60min from Shinjuku
then ropeway, or lift, or climb to Takao-san. Takao-san is not very challenging, but a nice start, and along the way there are temples and shrines. When at the top of Takao-san, one can also decide to go further: to one, two or even 3 mountains nearby. See Jinbasan notes.
There is a nice bath inside the Takaosan-guchi-trainstation.
a nice 4 hours trip, seeing Sagamiko lake, climbing Sekirouzan, Onsen visit possible
North of Tokyo
take train to Tsukuba trainstation(つくば駅), 60min from Tokyo
then enter the shuttle bus (筑波山シャトルバス) to 筑波山神社入口(Tsukubasanjinjairiguchi), takes 36min
then either climb up (90min) or take the cablecar (5min)
from there you can eat, and visit both mountains (takes 15min to each), or walk other routes
When going down again via cablecar or by foot, there are several Onsen. 3 are part of hotels and only open for non-hotel-guests until 3pm. A small onsen exists and is free for normal customers, also after 3pm.
From Tokyo, take the train to Doi-station/土合駅, takes ~3hours
from there, go to 谷川土合口駅 (24min walk, or by car)
from there a ropeway and chairlift go upwards
from the plateau it takes 3 hours of walking to the top of 谷川岳. Good shoes recommended.