Rules of exploration mode of Pathfinder 2e had recently puzzled me.
1. [Here][1] is said that every 24 hours characters need 8 hours of rest and if they'd go for more than 16 hours without it - they'd be fatigued.
2. [Here][2] is table of distances that characters can cover - and it's clear from that table is that per day characters are supposed to spend only 8 hours walking.

Is there any explanation about what happens during the other 8 hours before rest? Are there some mandatory activities that take those 8 hours? Is there limit on time of activity characters can do during day? Like - if characters spent 8 hours to reach some ruins - can they start exploring them? Because, according to rules of travel - they are too tired to walk anywhere by that time.

Thanks everyone for answering about what CAN be done during that time, it is going to help me set up some camp activities for player for sure.

But, I want to clarify that question is about what characters MUST do, according to rules. Is there anything that must take part of 16 hour-day that characters have, something that is written in official rules (or other official sources) that takes their time. Supposedly taking 8 hours that they are supposed to stay awake, but not travelling and whether it can be combined with some other activities (like exploring dungeons) or not. Alternatively - I'm looking for explanation (also official) - why travelling speed table lists travel distance per day as if characters have travelled only 8 hours per day.

Right now I'm aware that 1 hour per day is taken by daily preparations and unlike some other RPGs, daily preparations are not part of the rest
And that after 8 hours of travelling in fine weather characters are supposed to get fatigued (though fatigue shouldn't stop them from travelling, just limit exploration activities and impose AC penalty, but still in may be the reason for that travelling speed table to list only 8 hours of travel per day)


  [1]: https://2e.aonprd.com/Rules.aspx?ID=2443
  [2]: https://2e.aonprd.com/Rules.aspx?ID=2441