Newfound Gap Parking Area.
Parking spaces are abundant at the gap. The trail climbs 1000 feet in 2.5 miles from the gap to the branch-off at the Boulevard Trail. Ups and downs are common, but there are much more ups than downs. Once upon the Boulevard, you will descend 400 feet down the west flank of Mount Kephart. The terrain does not vary greatly. Upper elevation conifers are mixed with various hardwoods, graced by a carpet of grass and wild flowers. The trail is well maintained and easy to follow all the way. From this point on the trail is a veritable roller coaster (though slow) of ups and downs and ups and downs along the Boulevard ridge. At about three miles from where the turn off from the A.T., you follow the crest of a steep ridge, falling away on both sides: the views are gorgeous. Even those with a fear of heights should not experience trouble, however, as the trail is plenty wide. Ahead looms massive Mount LeConte, appearing just minutes away. Nay, there yet remains scaling the oft misty and wooded peak, two miles over and 750 feet up.
Aside from the A.T. to Charlies Bunyon and beyond, the only side trip here I know of is to the Jump Off. The Jump Off is a worthwhile thousand foot cliff and overlook a mile or so off the trail. An obvious sign will direct the way. The path is poor, often with downed trees to negotiate, but the view is wonderful. I recommend going to the Jump Off for a trip of its own rather than as a side trip to Mount Leconte. The Boulevard itself is quite a fine sequence of vistas, and considering the length of the walk, the Jump Off makes for a long day.
The Boulevard is often claimed to be the easiest of ways to LeConte. Let me state in no uncertain terms that this is not the case. The Boulevard is a very long hard haul even without a pack. I personally think that it is the most difficult, except for perhaps Porters Flat via Trillium Gap, which is longer and gains far more elevation. Nevertheless, I find the combination of many uphills and downhills to be more strenuous than even continual uphill.
However, the Boulevard is a "classic must do" kind of trail, and very beautiful. Just make sure you devote the entire day to enjoy it, lest weariness spoil the last few miles.