Check the NPS website to make sure that Highway 89 (the main road running through the park) is open. It is usually only open from June to September due to heavy snow pack.
A very short, paved, 1/4 mile trail to reach the base of the falls. You just don't see very many waterfalls like this in the world. If you are in the area, make the detour. We didn't camp here, but it looks like the camp sites are well maintained and plentiful.
The most rewarding hike of our trip. We opted for the Castle Crags Trail that leads to Castle Dome. You ascend 2200 feet in three miles (talk about sore legs the next day). You will need 4-5 hours to complete the hike because of its challenging climb, but the views are unmatched for the effort.
They filmed a few scenes from Jurassic Park 2 in this canyon - and once you are in it, you can see why!! You just keep expecting a raptor to jump out from every turn. Scientists estimate that some of the fern species in this canyon date back millions of years. Expect to get your shoes wet unless you are an excellent stream crosser.
The highlight of our trip. Although some groves further north are bigger, these are by far the most impressive. The trees up north have lots of underbrush that don't allow you to walk right up to them. The trees in the Avenue of giants have no brush underneath, just carpets of clovers. If you only have time to stop at a few groves, we recommend Founders Grove (home of the Dyerville Giant) and Rockefeller Grove (our personal favorite of the whole trip).
Totally kitschy but worth the $5 for 10 minutes of entertainment. You are here, you have to do it, because you won't be able to do it anywhere else. You also need the picture to prove it.
This was a total gem of a find. The owners (Sally and Sunny) are, ahem, quite eccentric. They met here in the 70's when the Howard Creek Ranch was a "hippie commune" (Sunny's words). The rooms make you feel like you are staying at your grandma's house - complete with shelves and shelves of knickknacks. Breakfast was nearly gourmet with cinnamon poached pears, sweet biscuits, sausage, and a mexican frittata. Bring your hiking books and walk the grounds filled with rabbits, sheep, goats, and chickens (OH SO MANY CHICKENS).
The ONLY time to go is at low tide (preferably with the tide coming in). If you go during high-tide, the "bowling ball beach" is totally covered by water. Don't know what Bowling Ball Beach is? Google it, then add this to your trip.
Spectacular whale and seal watching in Gerstle Cove. This park really lets you crawl right down to the tidal pools at low tide and poke around. Make sure you bring sunscreen and a hat - the sun is totally unrelenting with zero shade on the trails.
If you have the opportunity to head further north to the "real redwoods," DO IT. Skip Muir Woods and head up the coast. While it is a beautiful space, the loud families with screaming children and boardwalk really ruin the tranquility of the moment. The trees are also NOT NEARLY as impressive as those further north. If you are staying in San Fran and don't have plans of heading north, you should go - just to see the redwoods - it is still awe inspiring nonetheless.