Steel factory on Mars by Dmitrii Ustinov

Picture of the Day 15/01/2021 - Mars is about twice as rich in iron as Earth is; in fact its distinctive red color is due to iron oxides on its surface. So making steel shouldn't be a problem. Here is an artwork of a steel factory (mill) on Mars producing raw steel blocks by Russian artist Dmitrii Ustinov. More of his art here.

Lunar mining colony by Jort van Welbergen

Picture of the Day 8/11/2020 - Lunar mining colony with several landing pads for SpaceX's Starships (pictured here in their 2017 design, then called Big Falcon Ship) by Dutch freelance movie and game concept designer Jort van Welbergen. More of his art here.

Closeup of one of the Starship landing pads with Earth on the horizon:

Building an industrial complex on Mars by William Black

To survive on Mars longterm humans will need to live off the land (a practice in space exploration called In Situ Resource Utilization or shorter ISRU), so we will need to extract, process and store local resources of the planet. Here is William Black's artistic vision of building an industrial complex on Mars at Syria Planum, located south from Noctis Labyrinthus. More of his space concept art here.