I am built to remember a famous person or important event. People visit me and take photos. What am I?

A cat may wear me for a while, though only out of fright. An empire carved me into stone to honor glorious might.

Born in the dirt before the dawn of man I shake the mountains where I stand. I drink up rivers with my thirst, Of all God’s beasts, I am the first

I walk on four legs in the morning, Two legs in the afternoon, And three legs at night, What am I?

A red field's crown, A sleep of stone, A paper flower where grief is shown. What am I?