Stop in for a cup of coffee

Good Evening All! Mom, Uncle and 2 Aunts visiting this week, on huge road trip from Alaska/Canada. Uncle is an adrenaline junkie, runs marathons etc. Wants me to climb Everest with him (to the base camp 21K feet) lol! He's in his late 60's holy crap!
Everest is a quick way to die. I hope you explain to him that is NOT a good idea