Thank goodness there were not many visitors there.
Check it out:

A 4.8 earthquake shook the northern part of Yellowstone National Park early Sunday.

The University of Utah Seismograph Stations reports the earthquake occurred at 6:34 a.m. about 4 miles north-northeast of the Norris Geyser Basin. The university reports it was felt in the Montana border towns of West Yellowstone and Gardiner, both about 20 miles from the epicenter.

There were no immediate reports of damage. There are few visitors in the park this time of year.