The first stop in the morning goes straight to the Serab Museum. The museum is located in the northwest corner of Plaza de Espana, from sol down Preciados street to Callao Metro station, and then along Gran VIN street to Spain square, where you can find a person with a sign at the intersection. Around 11 a.m., you can visit it for free. I don't know if it's because it's always free on Sunday. The museum is a modern building on the outside, but it is retro and brilliant on the inside. The 17th Marquis of Sera, who lived here, made great contributions to poetry, painting, archaeology, precious stones, ceramics and so on. There were many precious exhibits on display. Eventually, the Marquis donated his residence to the government and was proud of the world. Personally, I like it very much. It's easier to understand and feel than Sofia.