California's finest: Yosemite Valley and Bridalveil Falls from the Tunnel View overlook.

On a whim, I decided to drive up to explore a spectacular stretch of California natural beauty for a four-day vacation: Sequoia National Park and Yosemite.

I hadn’t been to Yosemite for years, and I had never seen the Sequoias. Turns out that many of my friends had never visited the Sequoias either, though nearly all of them had been to Yosemite at least once. I would soon discover what we've been missing.

The drive up the 5 through L.A. and the subsequent rolling, golden hills is easy, but somewhat monotonous. Get plenty of rest the night before and don't plan to do much the same day as your drive. Once you arrive at Sequoia National Park, it’s like entering a different world.

Sequoia National Park

My friends in Visalia cleared me up on the main distinction between the sequoias and redwoods. “The redwoods are taller, but the sequoias are fatter, so they are the largest trees on earth.”

Some of the sequoias date back over 3,000 years and tower as high as 300 feet. They are fourth in height among plant species and first in total volume. Redwoods are the tallest trees in the world at 364 feet.

One feels humble in the shadows of the mighty sequoias. The trees inspire feelings of reverence and appreciation. Hikes tend to linger; this is not a place to be rushed.

The two largest (not tallest) trees in the world are here – General Sherman and General Grant, although the latter is actually in adjoining Kings Canyon Park. The General Grant tree, the tallest in Grant's Grove, is near a fallen sequoia named the Fallen Monarch, estimated to have tumbled around 300 years ago. I walked through its hollow interior.

Giant Forest in Sequoia National Park is where you go to see General Sherman, the largest tree in the world. The tree is a 15-minute walk away from the parking lot down a scenic trail. From General Sherman, you can hike the Congress Trail, probably the most popular trail in the park.

The climb up Moro Rock's 400 stairs reveals a spectacular view. If you lack the stamina to reach the top, you can still enjoy superb views along the way. Bring a camera to catch the sweeping vistas.

There are more than trees and hills to enchant visitors at Sequoia National Park. At Hospital Rock, there are petroglyphs left by the Western Mono Indians that date back to the 14th century.

Yosemite National Park

The following day after exploring Sequoia, I headed to Yosemite. Yosemite is, well, Yosemite – the most beautiful spot in America.

Despite National Geographic Traveler’s annointing of Dingle, Ireland, as the most beautiful place in the world, I’ll take the beauty of Yosemite over Dingle any day (though the latter is gorgeous and holds a place in my affection).

Arriving there was like revisiting – and rejoicing in – an old friend. Tunnel View remains in my mind the most stunning vista in America. The drive down into the Valley was as gorgeous as ever and brought back memories of my first visit there. I headed to the Mist Trail en route to Vernal Falls. This is one of the better short hikes in Yosemite, but it does require a certain amount of stamina; much of it is uphill.

Even on a busy weekend or summer day, you can find solitude on Yosemite’s many back trails. Early morning and dusk are particularly enchanting times, and it is unfortunate that so many day-trip visitors miss this.

It's worthwhile to drive up to Glacier Point for a spectacular overview of the valley, particularly in late spring when the waterfalls are flowing. It's also possible to hike down to the valley from there, but check the tram times so you can be sure to get back up to your car.

If you happen to be hosting an international exchange student (or other out-of-state visitor for any longer period of time) this summer, this is, in my opinion, the best place in California to take him or her. It's an unforgettable experience.

There is talk of restoring Hetch Hetchy Valley. It was the flooding of this valley to supply water for San Francisco after the 1906 earthquake that broke John Muir's heart. “No holier temple has ever been consecrated by the heart of man,” he mourned. Others have claimed that the beauty of Hetch Hetchy was equal to that of Yosemite Valley.

The most scenic entrances to the parks are Highway 198 from Visalia for Sequoia and Highway 41 from Fresno for Yosemite. It takes 5-6 hours to reach Sequoia National Park from San Diego and about 7 hours to reach Yosemite.

The best way to experience the parks is to camp. Check ahead for campground availability. It’s wise to reserve far in advance, particularly if you're going during the summer or on a holiday weekend.

But if reservations are booked, don't let it stop you. Look for rooms in nearby towns, surf a couch, or get on up there however you can manage. You won't regret it.