With more glaciers than any other peak in the contiguous United States and annual rainfall pushing over 120 inches in spots, it's not surprising that Mount Rainier National Park is home to countless waterfalls. Of the bigger falls,* Narada Falls is the Park's most accessible.
Just below Paradise Park, directly off the Paradise-Longmire Road, the two cascades that make up Narada Falls drop a total of 176 feet. The second and taller of the two cascades drops 159 feet and creates a curtain of white water nearly 70 feet wide.
To get the best view of the falls, walk down a short trail that starts at the eastern end of the bridge over Paradise River. This trail continues beyond the waterfall viewpoint and connects with the Wonderland Trail, which, when traveling westward, passes Madcap Falls (34 feet) and Carter Falls (54 feet). If you were to continue for 2.8 miles, this trail eventually reaches the Nisqually River at Cougar Rock Campground, making for a wonderful one-way day hike.
* The tallest waterfall in the National Park is Margaret Falls, dropping an impressive total of 1,350 feet from Cowlitz Park. However, Margaret Falls is essentially inaccessible, at least to the overwhelming majority of visitors to the park. The second tallest is Fairy Falls, which drops 680 feet from Williwakas Glacier (just below Paradise Glacier), but it is also inaccessible. The 462-foot Comet Falls is the tallest accessible waterfall in the park, and it is reached by a 6.2 mile there-and-back hike. The second tallest accessible waterfall is 354-foot Spray Falls, and it is accessed from the Mowich Lake trailhead via a 3.4 mile there-and-back hike.