It marks the official center of Madrid. Try to find the “km 0” plaque on the bottom, that is where all distances in Spain are calculated from. And even if you skip the tour, the outside is amazing By itself and worth halting by for images. AAPE membership is https://ifema-madrid-events58012.worldblogged.com/41884155/an-unbiased-view-of-what-you-need-to-exhibit-and-how-to-exhibit-at-ifema-madrid