Tolstoj is a large, ancient impact crater at latitude −15, longitude 165 on Mercury. The albedo feature Solitudo Maiae appears to be associated with this crater. The impact that produced the Tolstoj Basin occurred very early in the history of Mercury. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On Mercury they are named after deceased artists, musicians, painters, and authors who have made outstanding or fundamental contributions to their field and have been recognized as art historically significant figures for more than 50 years.
Image Source. Marker locations are approximate and may not always appear to align with image on map.