We have read that the traffic during the peak summer months can be quite dreadful since there can be up to a hour wait to get in and out of the park. We will be hiking in in the early fall just after labor day in order to avoid some of the crowds and hopefully have a better chance of staying within the park as opposed to having to stay outside of the park and driving in. Many of the parks features and best locations are accessible only by foot or bike and we plan on getting to those off the beaten path locations to really get the full experience. You can find all sorts of travel deals online for local attractions that can be found near you.
