Microfiber beach towels are the answer.

Yes. Get the quick-dry microfiber kind. They fold down to about the size of a paperback book, weigh nothing, and dry in the sun in ten minutes instead of staying damp all day.

Cotton beach towels are fluffy and nice, but they take up half your suitcase and stay wet for hours. Microfiber isn’t as soft—it’s more of a technical fabric feel—but for travel, that trade-off is worth it. You can even wring them out and throw them back in your bag without everything getting soaked.

I’d look for one around 60x30 inches or so. That’s enough to lie on without being a full blanket. Some come with a little carrying pouch, which is handy but not necessary.

Don’t overthink this one. Microfiber is the move.