D&D General Things to Find in a Large River?

[NotAYakk]

• A huge lake; think "great lake" from our world. Basically a freshwater sea.
• A tunnel where the river flows in/out of the underworld.
• A fork in the river
• A bridge built by giants. Humans have improved it/colonized it; the "steps" are 10' tall, human scaffolding makes them passable.
• Wetlands; a huge swamp.
• A canyon, where the shores mostly become cliffs, and the river cut a mountain in twain.
• A ford
• A ferry, that uses ropes and pullies
• A fort built in a rock-island. Has chains/arrows/rapids to prevent bypassing it.
• A strange people who get their food from large, electric stone mushrooms. They believe in eternal life/reincarnation. One of them is building an airship.
• As noted, cataracks. Above/below can be very different.
• A flat flat plain, where the river meanders and moves over the land, and crossing a 100' shortcut can save days of river travel.
• Were-weasels, were-crocs, were-hippos
• Electrix eels.

 

[Bohandas]

...So tempted to ham it up with flying pyramids.

Have you ever seen the movie Kung-Pow: Enter the Fist?

 

[Zardnaar]

Have you ever seen the movie Kung-Pow: Enter the Fist?

Nope. Haven't even heard about it.

 

[Rob Kuntz]

Derelict ships; notorious smugglers; murder victims; various haunts and ghosts associated with their dying upon it; and more empty wine bottles...

 

[Eltab]

• A dam across the river
• Logjam
• Snag (single sunken tree with trunk pointing up)
• A piece of equipment that should have rusted / rotted away from being submerged so long, but hasn't. This is a hint that the item is magical.
• Cleric or paladin of the river god is the local law enforcement troubleshooter. He has a swim speed and can call river animals to aid him.
• Papyrus plantation along a swampy shore
• Royal hunting preserve, well stocked with dangerous beasts. Killing one (even if it is attacking you) is considered stealing from the king.
• River water changes color for some reason
• A famous shipwreck. Not just 'a freighter' but the Edmond Fitzgerald
• Sunken barge had a completed but undecorated obelisk aboard.

 

[Beleriphon]

• A strange people who get their food from large, electric stone mushrooms. They believe in eternal life/reincarnation. One of them is building an airship.

I feel like this is a reference I should be understanding, but I'm missing it completely.

 

[Hussar]

I feel like this is a reference I should be understanding, but I'm missing it completely.

Very excellent series - Riverworld by Philip Jose Farmer. Check it out. It really is excellent.