Every river on Earth — from the mighty Amazon to the creek behind your house — is on a journey to the ocean. They twist through forests, carve canyons, rush over falls, but they all end up in the same place. What's pulling them there?

The answer is gravity. Gravity is the force that pulls everything toward the center of the Earth — it's why dropped keys hit the floor, why rain falls down instead of up. Water obeys that same pull, always flowing from higher ground to lower ground.

Rivers start high up — in mountains, on hilltops, anywhere rain collects or snow melts. Up there, the water has only one option: roll downhill. It finds the lowest path available, the easiest groove to follow, and starts moving.

Now here's the key: the ocean sits at the lowest point on Earth's surface. All the land — mountains, plains, deserts — rises above sea level. So when water flows downhill from anywhere, it's flowing toward the ocean, whether it knows it or not.

The river doesn't "choose" the sea. It just keeps obeying gravity, step by step. It flows from the mountain to the valley. From the valley to the plain. From the plain to the coast. And the coast? That's where the ocean waits, the end of the downhill path.

Sometimes a river hits a lake or an inland sea along the way and stops there — like the Jordan River ending in the Dead Sea. That happens when the lake sits in a basin with no lower exit. But most rivers find a path that keeps going down, all the way to the ocean.

Once the river reaches the ocean, the water doesn't stop existing — it just joins something bigger. The river water mixes with the salty sea, and the journey changes. Now the sun will evaporate some of it back into clouds, which will rain on mountains again, and the whole cycle starts over.

So rivers don't "choose" the sea because they're romantic or poetic. They flow there because the sea is downhill, and water always flows downhill. Gravity writes the map. The rivers just follow it, one slope at a time, until there's nowhere lower to go.