It’s the last undeveloped parcel on the prestigious Capitol Mall … with no height limits … and it’s right by the Sacramento River. Called Lot X, it’s a little larger than a city block, and across the street lies the heavily treed Crocker Park … and the Crocker Museum that will receive millions from the sale of Lot X, toward its coming expansion. Lot X is now used for parking. Real estate brokers say it would probably become a high rise with office space, a hotel, or condominiums … or a blend. With the 53-story Towers condominium project just up Capital Mall, Lot X might well become home to a companion skyscraper.