According to SanFermin.Com, reserving a balcony spot is the best way to view the Running of the Bulls.

The alternative to watching the encierro from a balcony is to stake-out a spot at the wooden barriers that exist at a few areas along the route. In order to get a good spot, you will likely need to stand in-place (at that spot) for more than two hours prior to the run. Also, watching the run from ground level severely limits the amount of action that you can see.

If you reserve a balcony spot, you will spend the morning relaxing in an apartment, enjoying wine and sangria with your hosts. When the run begins, you simply step-out on your balcony and enjoy the show...

(The balconies featured on this page are not ours. Ours is better.)