The key to packing properly for your Belize beach or jungle adventure is the laid-back style of the country. Unless you are traveling for business, leave your dressy options at home.
Inland adventures usually require hiking gear like lightweight long pants and long-sleeved shirts, strong hiking boots, binoculars and a bathing suit (to plunge into the green pools at the base of waterfalls). Bug repellant is also necessary but can be bought in most tourist facilities and supermarkets in the country. Flashlights may also be required to explore the numerous caves. This is often provided by the tour operator or resort but can also be bought in any hardware store or supermarket. Early mornings and late evenings may become cool in the mountainous regions, so a simple jacket or sweater should also be packed. Depending on the time of year for your visit, rain gear will be a welcome addition to your vacation.