I know that this is an off street, urban public transport on electric traction, which is located in Moscow and partly in the Moscow region.
If you want detailed information, you can find it below. The information is partly taken from the Internet, I paraphrased it to my disposition, so there is no point in complaining.
The first line of the Moscow Metro was opened in 1935. Today Moscow Metro is the 5th busiest and the largest in the world. Many metro stations are sightseeing places. They look like subway palaces. The Moscow Metro consists of 13 lines with 203 stations (2017). Almost all of them are underground. During peak hours the minimum interval between trains is 90 seconds. There are 7 million people riding in the subway every day. The most popular metro stations are Pushkinskaya, Kitay-gorod, VDNKh, Prospekt Mira (Prospekt Mira), Lenin State Library, Arbatskaya, Botanicheskaya garden and many others. The Moscow Metro is one of the most beautiful in the world. Muscovites and guests of the city meet here with an outstanding work of architecture, the most interesting museum of beauty. Marble, granite, non-ferrous metals, frescoes, mosaics, carving, metal and stone, sculptures, the whole architectural ensembles - all this gives the Moscow Metro unique features. For many, the Moscow Metro embodies everything that is great and beautiful in Russia.
Unfortunately, I cannot answer the second question because I have no idea about the Palace of Congresses....
Good luck to you,my dear friend