Mysterious objects on the beach 🏖 What on earth is this?

Can somebody please tell me what these mysterious objects are?

Last week I embarked on a road trip to Mozambique in Southern Africa with my family. We decided to go exploring along some very challenging 4x4 routes until we came across a nice spot to stop and swim in the ocean. As we walked towards the ocean from where we had parked our car and started to see more of the beach, the first thing we noticed was these three large, cylindrical rusted metal objects.

As you can see here, this has been here for quite some time and is possibly from a shipwreck.

This above picture just shows where these objects are relative to each other and their surroundings.

Since the rust has eaten away at the metal in this particular way, we can see that there is what seems to be a ladder hidden beneath what seems to be some kind of manhole cover which leads me to believe that these objects travel far beneath the surface.

This one in particular seems to be far less eroded than the other two. Perhaps this isn't part of a ship at all? Perhaps these were built to access something bellow the surface of the beach?

As you can see this one has undergone far more erosion than the other two.

I just wanted to include this image to show the size of the three objects relative to my sister so that you can get an idea of the size of the objects.

I hope that you enjoyed this post and I hope I've given you something to think about.

Please leave a comment underneath this post of what you think these things could be.

Also, If you are like me and cannot see what these are, give this post a resteem so that it can be exposed to more steemians!

Lets solve this mystery!

@rob99