If you live in America, you can travel a ton and meet tons of different people and cultures and live outside one's comfort zome IMO. There are a ton of (unfortunately underserved) reservations to visit filled with peoples coming from a completely different history and culture. One can travel to a church of a religion one doesn't follow (jewish, sikh, buddhist, pagan, catholic, muslim...), go and worship with them in their sacred holidays. If you're from west, go east, and vice versa. If you're from the north, go south, and vice versa. There's BBQ competitions and dance competitions, buffalo wings and gumbo, rodeos and derbies, BDSM meets and city halls. Volunteer at an animal shelter. Volunteer at a planned parenthood. Volunteer at a soup kitchen. Volunteer at a furry convention.

These will all broaden your horizons equally well as flying to another country. It's showing you your own country as an infinite fractal of human experience.