I've received this one from Ula! It shows the coronation sword of the Polish kings, 1st half of the 13th century, which stays in Royal Treasury, Wawel, Cracow.
I've received this postcard from Francisca! It's about Sintra, according her, one of most beautiful cities in Portugal; she told me about the "travesseiro de Sintra", which in english means Sintra's pillow.
This one was sent by Poom! It shows, again, the Wat Phra Kaew, in Bangkok, a part of the grand Palace; according him, it's the most beautiful temple in Thailand.
I've received these postcards from Mohamed! Well, I think the both dispense more information, but, anyway, the above is about the famous Giza Pyramids and, on the right, the Golden Mask of Tut Ankh Amoun.
This one was sent by Natasha! She lives in Ukraine and sent to me this drawing by Marysya Rudska which, unfortunately, I couldn't find any information.