Unless you find a handy tree or wish to play around with kites, you're going to need some sort of antenna mast. It can be fairly light and flexible if you're just using end-fed thin wire antennas. On the other hand, if you'll be using heavier wire antennas or even beams it will need to be more solid.
Below are videos of various poles and masts I've used for portable and home operating.
Compact telescoping poles - how good for portable antennas?
5m aluminium antenna mast (sold by Jaycar, Australia)
Home station timber antenna mast
... and how you can best use the bits remaining
PS: Antennas to suit these masts are covered in Hand-carried QRP Antennas. Available in electronic and paperback form (some countries) this well-reviewed book is a popular read amongst hams who go portable.