Krka National Park is not exactly on the Dalmatian Coast, but its most popular part is located very close to Šibenik. That part is called Skradinski Buk waterfall area ♥♥♥, accessed either through Lozovac entrance or via a boat from Skradin. It is not too large; the whole circuit is just 2 kilometers long, with not many steps up or down, making it walkable even for children or people in indifferent physical shape. The route is very picturesque, with many gorgeous viewpoints. There are nice amenities, including a large food court, and some food sellers suitable for a picnic.
The defining feature of this park area is the swimming beach by the waterfalls, which is not actually all that great, because of large rocks under the surface; water shoes are essential, and skinned legs and stubbed toes are practically unavoidable.
There is a limit of how many tickets to the park are sold every day, and although the counter at the reception still showed a couple of thousand of available tickets in the afternoon, the park still felt fairly crowded in early July. Everyone says that crowds at more iconic Plitvice Lakes are worse in the height of summer.
There are some options to take boat tours on the lakes, which we did not take advantage of. The same ticket allows entry to the other parts of the overall Krka Park (there are three or four designated visiting areas in addition to Skradinski waterfalls), for those interested.