The opening scene with a teenaged Indy stealing the Cross of Coronado from a group of adults by making his way through a Circus Train, getting traumatized by snakes and taming lions along the way. In the end, he has to give up the cross. The fedora guy gives him his fedora, and when he looks up...
Better still, Indy finally completes his personal obsessive quest after that Age Cut, besting his oldest foe and closing out that chapter in his life.
Indiana Jones on a horse vs. a tank and three trucks all full of Nazis. He tricks the tank into running over one of the cars, stuffs a rock down the side-cannon's barrel, jumps onto the tank, fights the Nazi Dragon, shoots three Nazis in one shot, throws the gun down to his dad so he can kill the Nazis in the tank and blow up the other truckload of soldiers (all while still getting beaten on), falls off of the tank into certain doom, gets back on anyway, chucks his best friend off the tank, saves his dad from being run over by the tank while the Dragon is still breaking ribs, manages to get his dad off of the tank, and manages to jump off himself just as it falls off a cliff taking the Dragon with it. And of course afterwards when everybody thinks he's dead, he climbs back up.
Made even more awesome by the fact that just before he realizes, "this tank is going off a cliff and I need to get the $#**% off", his trademark fedora gets blown off in the wind and we think "Oh no, is this the end?". Then when he gets back off the cliff, bruised, bleeding, and for crying out loud just plain exhausted, with a look on his face that says "Hey, you guys go on ahead and find the Holy Grail without me, I'm just gonna lie down and die", his fedora blows back onscreen, he gives it a look, and resolutely puts it on and goes to join the others. Maybe Hitler declaring war on him wasn't such of an overreaction after all.
At one point during the tank scene, Marcus actually managed to knock out a Nazi soldier in the tank by lightly hitting him with a used canister shell, and as the soldier was knocked unconscious, he ends up accidentally firing the pistol he was holding, which then kills the driver of the tank after bullet goes around until it hit the driver's head, which then his limp body ends up causing the stick that controls the direction, and makes the tank go right, saving Indy from being crushed by a rock wall.
Those crazy Knights Templar booby traps. When will they learn that you just can't get rid of Indiana that easy?
This Troper views Indy's decision on the final trap - a literal leap of faith - to be a crowning moment when you see it for the first time, because you can't see how in the Hell Indiana can cross a vast chasm. The moment he lifts up that leg and prepares to leap off, you HAD to be on the edge of your seat thinking "How is he going to survive THIS one?"
Hey Indy, I bet you can't joust on a motorbike with a flagpo- NO WAY!!! Well, I bet you can't jam a flagpole into one of the Nazi biker's tire's and flip it ove- WHAT THE %$@*#!!! THE MYTHBUSTERS SAID THAT WAS IMPOSSIBLE!!!
It's one of the few times his dad(a professor of medieval studies) is impressed.
Indy finally getting back the Cross of Coronado from Panama Hat after 26 years.
The Leap of Faith, and the accompanying music.
Sallah gets one. While The Nazis and their escort are visibly freaked out after watching the Grail heal Henry. Said Cohorts run like hell out of the temple leaving only the few Nazis left. Sallah takes the chance to hold the remaining few at gun point and making them drop their guns.
Sallah: Drop your guns....please.
The ending ITSELF is an awesome moment. Watching the heroes ride off with the theme in full force leaves you feeling empowered! Also a Crowning Moment of Heartwarming.
For years, Steven Spielberg was against making a fourth movie; that image was the perfect note to end the series on.