www.nps.gov/...visit/rangerprog.htm
et apres, par example, cliquer: "Fishing Bridge/Lake Village"
du lien ci-dessus:
"Wildlife Watching in Hayden Valley Starting June 12
Observe wildlife from a scenic point overlooking Hayden Valley and the
tranquil
Yellowstone River. Be prepared for a possible short stroll, over
steep terrain, to the river. Meet at the large pullout in Hayden Valley, about
10 miles north of Fishing Bridge Junction and 6 miles south of Canyon
Junction. Easy 1½–2 hours"
La plupart des activites organises sont gratuits et sans reservations.