Apologies for the long silence. I’ve had some difficulty finding suitable onsen(s) since my original choice(s) did not seem suitable but I have now selected the following.
Post-Do 6-7 April (one night)
Tamatsukuri Onsen Chorakuen
https://www.choraku.co.jp/en/
Select Breakfast and Dinner Plan under Plan List. The price will be ¥30,250 (plus ¥150 onsen tax) for one person in a room, or ¥22,550 (plus ¥150 onsen tax) per person with two people in a room. They only have a few rooms left but I believe there will be a few of us on the post-do Onsen trip. I suggest anyone interested should book as soon as possible.
Tamatsukuri Onsen is one
of the oldest onsens in Japan with a history dating back to at least 733 AD, where it was introduced as “The Bath of The Gods” in the Ancient Chronicles of Izumo. It is near the city of Matsue and is about 4 hours from Hiroshima by bus or train. More on travelling options including the use of a regional rail pass in a separate post.
Please see
post #164 for travel information.
Also if anyone is interested in a second Onsen in the area please see a separate post.

Tamatsukuri Onsen

Rotenburo at Chorakuen - the largest open-air hot spring for mixed bathing in Japan!