A rare opportunity in one of Greenwich's most coveted in-town settings. 21 Calhoun Drive combines the presence and character of a classic Greenwich estate with exceptional privacy, generous scale and close proximity to everything that makes Greenwich living so desirable. Set amid mature landscaping on an oversized approximately 1.8-acre property in a one-acre zone, the estate offers nearly twice the typical lot size and exceptional flexibility for the future. Gracious entertaining rooms, comfortable everyday living spaces and architectural details give the residence a depth and personality rarely found in newer construction, while the established grounds provide both privacy and room to further enhance the property. What truly distinguishes 21 Calhoun is the opportunity it presents. Offered with a building permit and engineering for a guest house, the property provides the flexibility to enjoy the existing residence, thoughtfully expand over time, or create a substantial multi-generational Greenwich compound. The oversized acreage also creates compelling possibilities for additional outdoor amenities, including potential sports or recreation areas, subject to applicable requirements and approvals. With its established residence, unusually generous acreage, valuable planning already in place and significant future potential, 21 Calhoun represents a compelling opportunity to acquire a substantial Greenwich estate at a value increasingly difficult to replicate. A property to enjoy today, enhance over time and make entirely your own.