Here are several items that could have come from a single, somewhat circuitous, trip in around 1960. (But they didn’t; I received them from multiple sources.)
Inside the envelope are your tickets, including this ticket (probably just the stub left you after the conductor took your ticket) suggesting you are traveling on the City of Portland to Denver. The ticket stock is dated 1959, and the date of travel is June 13. The City of Portland didn’t originally pass through Denver, but in 1960 it was rerouted and merged with the City of Denver, so this ticket is probably from 1960.
You probably fastened a baggage tag like this one to your bag. The tag has a 1958 date on it, but the railroad probably printed 100,000 of them, so they probably lasted for several years.
Perhaps later in your trip you ride the City of Denver and receive this card indicating you’ve made reservations in the diner. (In fact, this card is probably from before the train was merged with the City of Portland.)
You might have decided to make your return trip via San Francisco. The railroads often allowed passengers to take multiple routes for little more than the cost of a round trip on the same route. This early dinner menu is dated 1959.