The internship took place in Madrid from 3/2020-7/2020. It was scheduled for 3 months but in the end due to corona pandemic lasted 4 months. I was meant to work both in the UPM and INIA for the same amount of time but due to pandemic I was working mostly from home. My project was to assess if the species Pinus pines is a good indicator of mercury bioaccumulation by studying the cores and separating them every 5 years needles soil and bark of specific urban areas in Madrid and one clean reference area outside of Madrid. Then I was carrying the specimens inside a DMA 80 (Direct Mercury Analysis machine) to count the mercury inside them. Although I spend most of the time in the house working from there I had the chance to see both facilities, my co-workers were very friendly and helpful, the facilities were pretty cool, the city was amazing very warm, fun and friendly people. I enjoyed the procedure of the project and all the new things I learned, even though it could be a lot better without the pandemic.