Nice trip! Check out a Rootless fire pit for places without rings, rocks or you otherwise want to LNT. Packs up small. Not going to work over dry grass, but does a good job keeping a fire contained without leaving a mark. Surprisingly sturdy. Have used mine over and over without issue.
I use something similar. Nice for places that don't already have a pit or if the existing pit is a pit. A lot sturdier than I thought it would be and folds up into a small cylinder. Have used it loads of times with no noticeable wear. Amazon link
We have had good luck with this one. It’s surprisingly sturdy. $50 https://www.amazon.com/dp/B07D34J96Q/ref=cm_sw_r_cp_api_glt_fabc_K5JDX1R1890Z5KJHKBFD?_encoding=UTF8&psc=1
I use a Rootless large fire pit when there isn't an existing ring. Similar to what /u/mcwelby6 recommended. Works great. Much more durable than it looks. Had mine for some time and no issues after many uses. Nice thing about it is it rolls up for easy storage. Down side is it burns wood pretty quick given all the air flow. Not so great if it is windy.