Firstly, if this is a must see, be sure and ask the ranger for a pocket trail map when you drive…read morein.
The ranger handed us one when we arrived at the Wawona Gate and told her we hoped to find parking at Mariposa, since the weekend proved too crowded (folks were parking along the main road and walking uphill to the Welcome Plaza, something that would have been too much of a challenge for us in the midday sun). She assured us it was much less crowded this Monday morning, and handed us the pocket map, which became very helpful, once I remembered it was actually IN MY POCKET!
This is the first time I've been able to see this grove of Giant Sequoias in Yosemite. It reopened in June 2018 after a long closure and refurbishment to allow better access while protecting the trees in their ideal conditions - meaning, keep humans at bay.
When you arrive at Mariposa Grove Welcome Plaza, there are nice bathrooms and a small bookstore, sundries, souvenir shop and information about the various hikes, maps of trails(I suggest taking a pic of, if you don't have the pocket map), and volunteers happy to guide you through hiking options, or easy routes to just see the largest of the popular Sequoias, Grizzly Giant. You catch the shuttle here for the 6 mins ride to the trailhead for Mariposa Grove, Big Tree Loop and Grizzly Giant Loop trails.
We opted for the "moderate" hike along the Mariposa Grove Trail to Tunnel Tree, in which we saw the famous Grizzly Giant as well as the notable Bachelor and Three Graces trees. Our elevation gain was about 300ft. We then continued .2 miles to Tunnel Tree. After queuing for our turn to take pics, we added on treks to see Faithful Couple and Clothespin trees and still found it mildly challenging, but not strenuous. I believe we hiked a total of 1.25 miles up, then it was all an easy downhill back. This total visit, with shuttle rides up and back, took 3 hours. We did not find this to be "moderate," but rather enjoyable and only slightly more challenging than a level walk around a forest. My friend often has to stop periodically for heart rest breaks when hiking, but didn't need any breaks on during today's hike.
Take plenty of drinking water with you and maybe a light snack. If you need a restroom, try holding out for the ones at the Welcome Center. The set up at the shuttle pickup/drop-off were not as well maintained, lacked TP, had on stall marked "Closed for the Season," like THAT would be a thing, and defunct hand dryers, but no paper towels.
All in all, if you're a fan of Giant Sequoias, you'll want to add Mariposa Grove to your list. We are hitting all the Giant Sequoia areas we can during this road trip, so I would say, comparing the 2 so far, Calaveras Big Trees Park was more enjoyable and an easier tour of these amazing Goliaths, but soon we will add Sequoia Ntl Park & Kings Cyn, so THEN we will know definitively which park towers above the rest. Cheers! "CC"