Depends a bit, whether a day visit, overnight stay, established resort, ad hoc, with tent or in a flat/bungalow etc. Either carry along somehow (many different options on how). Common also is to stick it somewhere around (under porch mat above front wheel of the car, into the trunk etc, under the tent or into a pocket of a portable chair).
Fanny Pack???!!! ha ha ha I guess this is where American English can cause us British to laugh .... a "fanny" in British English is a woman's lower front part! We would call them "bum bags", which is just as silly.
Bum bags? That makes me picture a hobo trudging down the road with his bag on a stick over his shoulder.
I never went to a resort to spend only one day, but I always leave clothes at the car when I go to a nudist place... you can bet I will drive this travel naked so I leave clothes in the trunk... who cares in a nudist place if you get out from your car naked... I always do except in a natural park where there are a lot of cows roaming freely to avoid show to the rest of the people how I can run naked when I have a cow following me... the best you can carry is a back pack with a towel, water, a book and keys... and you can always use it as a pillow in long stays... you never know how nice fit it in a naked hiker ;-)
My textile exoskin goes in the trunk. The key and remote are usually in the goodies bag, or on a lanyard around my neck when I go to the car to fetch something from the trunk. This hat ...... has a built-in zip pouch for keys, loose change, etc.
I have seen those hats, and that is an awesome idea! I need to get me one!
The couple of resorts I go to, I keep it all in the car and if I need it, I go get it. i doubt there are two many car break ins at nudist resorts.
At "clubs", sometimes called "resorts" ... our clothes are left in the car. We don't take many valuables with us to our club ... not because it isn't safe ... there's just no need for us to take them. Aside from your ID and a little cash for the cafe ... we don't take much in the way of valuables. Those that we do take are in a bag we carry our towels, sunscreen, fly swatter, foam can holders, towel clips ... What's not in use ... goes in the bag. Resorts; we've been to several. Those we've gone to and spent the day are a little different. One smaller resort has a "Day Use Room." One room is designated the Day Room for those visiting for the day. You have use of the entire room EXCEPT for the beds. Makes it nice to go in and leave your things, use the restroom, the shower, microwave, coffee machine, small refrig. Another resort we used to visit frequently had small 12" x 12" lockers ... conveniently located right next to the hot tub. My wife hated that! I didn't care for it much either. Such a beautiful resort and plenty of rooms to designate 1 room a day for Day Use but you felt like you were putting on a Strip Show for the people in the hot tub. We'd get there, and there would be conversation going on in the hot tub. The minute my wife began to take off her sundress ... ALL talking stopped. I looked over at the hot tub and the 3-4 guys in the spa suddenly turned away and began talking again .... idiots! I've always felt that our belongings were safe at any club or resort.