>>1493057I do these when my wife wants to hike too. Pic related was taken during last week's hike. I put him back where I found him.
As a rule we carry a gallon of water each (desert hikers) but never use more than half that. I carry a separate 20 oz bottle so I don't have to pull the gallon out every sip; you may not need all that given the temp you posted.
For just-in-case, I have some basic first aid items such as EpiPen, gauze and bandages, duct tape, benedryl and Tylenol, quickclot, and some neosporin. As a water backup I bring a life straw. I keep a 2 layer Columbia shell with an extra pair of socks in my bag in case I'm caught overnight or in rain unexpectedly. I also take a box of aluminum foil (field expedient cookware), knife, and tiny fire-making kit, just in case. Finally, I have a small trowel, roll of TP, and wet wipes in my bag with some gallon ziplock bags so I can take a dump ethically if the need arises.
Food-wise this is like any other /fit/ activity, calculate how many calories you will burn, and bring that much food (according to your caloric goals and subtracting what you will eat when not on the hike). For me this is usually a couple PB&J's, jerky, and granola bars. If you are doing a strenuous 6k, you may want to top up on complex carbs in the AM and the early-hike snacks to keep your energy levels up consistently.
All of this fits in a 20L bag tightly, or 45L with lots of room to spare,and weighs about 12 lbs with the 45L bag. I put my wallet and keys in ziplock baggies, any paper map in its own ziplock, and phone on airplane mode (also in a dry-bag). I always bring a compass as well, though it's hardly ever used on these shorter hikes. It weighs so little though there's no harm in having it regardless if you haven't hiked this route before.