Identify the part of speech for underlined phrase was similar to the one he had seen in yellowstone national park

I managed to find the exercise online - you are supposed to determine what type of a noun Yellowstone National Park is.
The correct answer is a proper noun. Proper nouns are used to denote names; names of people, animals, geographical locations, rivers, parks, etc. So given that this is the name of a park, it is also a proper noun. 

Dr.king , i would take my mental flight by egypt and i would watch god’s children in their magnificent trek from the dark dungeons of egypt through, or rather across the red sea, through the wilderness on toward the promised land.his  speech"i  have a dream" to encourage people that change will come. this  speech  was very important during the civil rights movement and was a contributing factor in the end of racial injustice in society. the  intended audience  of "i  have a dream" is white people. i hope this