Question

What is an obelisk how tall is it

Answer 1

A tapering stone pillar, typically having a square or rectangular cross section, set up as a monument or landmark. Usually about 10m high.

Answer 2

Although the earliest obelisks were a little over 3 meters tall, or about 10 feet, they gradually became taller, reaching about 30 meters, or around 100 feet, in height.