Stand up Paddling is a watersport where you train your paddle power, balance and whole upper and under body by paddeling on a bigger kind of Surfboard with a paddle. You can perform stand up paddling on every lake, pond or ocean. It's alowed almost everywhere. Normaly you can say, the bigger the board the more volume and floatation you have.
There are two kind of different SUP lines on the market. The SUP's which are inflatable, and the stiff or hard SUP's which are perfect for paddeling out to the ocean or to the next break to surf all the way back in with longboard kinda style.