Wanderlust World Wanderlust World Somerville and Boston are adjacent cities (Somerville borders Boston proper). A standard First-Class letter mailed in Somerville to a Boston address typically takes 1 business day. If mailed early in the day, it may arrive the same day. Maximum 2–3 business days for any USPS First-Class Mail within the same metro area. Factors: drop-off time, processing plant routing, weather.