What are those triangle/pyramid-shaped pylons called? Are they even pylons?
They aren't steel transmission pylons. These are very tall, supported by central poles and wires that go all the way to the ground like tent strings. They seem to be wired together by hanging poles that look like trapeze swings. I've only ever seen them clustered together in one place, and they vary slightly in height but look identical. I used to think they were the tops of boats or ships.
What on Earth are they and what are they used for?