i think it would definitely fit a beach towel if you rolled it up and put it in there.... i haven't put anything together yet but i bought the following to put in there, individual advil, alkaseltzer and immodium packets (drugstore.com), wet ones, tissues, first aid kits, a little booklet of spanish phrases (i put it together myself instead of spending money on one, then just ran them through a copier with a cute icon), a welcome booklet of the week/weekend events and important information, tropical pens and a note pad, "to have and to hold and to keep your drink cold" beer coozies (oriental trading, cheap for 50), playing cards, lip balm with spf, and i am going to order 22oz plastic mugs with our names/wedding stuff on and put 2 in each bag, thats all i have so far... i started buying stuff months ago so that i could have a bunch of stuff to put in there... i also got these cute little maraca key chains that i am going to attach to the handles of the bag for a cute little touch (amols.com).... thats it so far, and might be it... it is very easy to keep spending and spending on these bags! haha!