Markley Group — One Summer Street

Markley Group, an independent operator founded in 1991, has run its flagship data center at One Summer Street in downtown Boston since the facility launched in 1998. The company describes it as the largest independent data center and carrier hotel in New England, spanning 920,000 sq ft, with a 2N electrical architecture and a bi-directional chilled-water cooling loop fed by five independent chiller plants in an N+1 configuration. More than 90 network carriers are present in the building, giving it a role as a regional interconnection hub comparable to the carrier hotels found in larger US metros. No absolute power figure in MW is published on Markley's own site — trade press has cited up to 30 MW at various points, but that figure is not confirmed by the operator directly and is not used here. Markley holds company-level ISO 27001, ISO 27701, SOC 1 Type II, SOC 2 Type II and PCI DSS attestations and states HIPAA and GDPR compliance, but no Uptime Institute or TIA-942 Tier certification is published for the site. The company also operates a second, physically separate building in Lowell, Massachusetts (a converted former Prince Spaghetti factory) used for expansion and disaster-recovery capacity, giving Markley a two-site presence in the Greater Boston market distinct from the large multi-market chains already in this catalog.