The iceberg that sank the Titanic a rather flat shape, and was sitting relatively low above water, making it quite hard to spot during the moonless night of April 14th, 1912. A dark mass a ocean.
Which iceberg was it?
The morning after the Titanic sank, rescue ships who answered the distress call spotted several icebergs nearby. The iceberg pictured on the left is often labeled the one that sank the Titanic, most notably due to a streak of red paint described on the berg. However, this particular iceberg is spiked, allowing it to break the horizon in the crow's nest, where it could be seen by lookouts quite easily even a moonless night since the spike would have blocked out stars on the sky.