If you ask most people what sights you can see in the Politechnika area, they will probably answer that the spot is not worth the shot, that you should probably get off a stop before/after to check the MDM (check out the article) in Plac Konstitucij, or maybe check the park Pole Mokotowskie, full of events in summer.
Well, if you decide to have a walk in the area, there are several nice spots, including bars, restaurants (some of them also spotted) and a beautiful building inspired by the Italian renaissance just around the corner.
The construction of the Politechnika building started in 1889, but it was heavily damaged during the WWII, as was most of the city.
Nowadays, the building hosts the main headquarter of the University of Technology, a square full of students, with lamps that are reminiscent of the early 20th century and a facade with impressive sculptures that will take you back in time.
Personally, I find the most interesting part of the spot to be the interior — the building can be easily accessed and is often used to host events and concerts in the big patio covered by the colored glass roof in the picture.
This is why people love Warsaw, it is so modern but turn the corner and you will find a hidden gem to travel back in time.