This is when the train crashed in Weekenders Adventures of The Rugrats Movie.

(Cut to a train, which pulls into a station. 2 men, Serge and Igor, leave the locomotive.)

Igor: Serge, you stay here and watch monkeys, I get us coffee.

Serge: No, Igor, you stay and watch monkeys and I get us coffee.

Igor: Nyet! Monkeys watch you, I GET COFFEE!

(Cut to interior of diner, where both men are enjoying their coffee. Igor drinks from a cup, while Serge drinks from a dish. Both are also eating donuts. Their train is in view through a window as monkeys climb out and on top of the train.)

Serge: I think coffee's better in St. Petersburg.

Igor: Nyet, is better in Kiev.

Serge: No, it's better in St. Petersburg!

Igor: Nothing is better in St. Petersburg!

(While the men argue over coffee, the train begins to move. Serge does a spit-take.)

Serge: Look! The train!

(The men rush out, bumping over tables and other customers.)

Serge: Let me out! Stop!

(By the time Serge and Igor get out of the diner, the train's already racing off into the distance; Igor rants angrily in Russian and throws his hat to the ground and stomps on it.)

(Cut to the train still rolling off. Inside the train, it's revealed the monkeys have commandeered it. The lead monkey who is driving the train puts on an engineer's cap and smiles. Another monkey pushes a lever that increases the train's speed. After it passes a flashing "Danger, Slow Curve" signal, the train derails and crashes into a vast forest. Before we fade out, one of the monkeys climbs out, bewildered.)