On the defensive side, Stalin had made equally thorough preparations. Lenin’s personal guard consisted of two men, later increased to four after the attempt on his life by Fanny Kaplan. Stalin’s was several thousand strong, and the NKVD in addition kept other units at a state of readiness. The road to his country dacha, some twenty miles away, was guarded by over 3,000 agents, with cars, telephone connections, etc. When Stalin was actually en route, the road was virtually under martial law.
1968, Robert Conquest, The Great Terror: Stalin's Purge of the Thirties, Macmillan Company, pages 546–547