To light the way for nighttime visitors, the High Line has more than 4,000 energy-efficient LED fixtures beneath handrails on both sides of the 1-mile-long park. L'Observatoire International, a New York City lighting design firm, devised the system, which is controlled by an astronomical time clock and a photosensor. The 12-person company was founded by Hervé Descottes in 1993 and works on dozens of projects worldwide each year, including Beijing's Linked Hybrid towers in 2010.

Decking and Benches
The park's wood decking and benches must be able to withstand New York's humid summers and dry winters. TerraMai of Medford, Oregon, reclaimed 9,000 board-feet of teak, known for its resilience, from abandoned sheds, barns, and warehouses in Southeast Asia for Section Two of the park, which opened in June. Richard McFarland and Erika Carpenter co-founded TerraMai in 1991 and sold it to current CEO Ken Westrick last year. The 25-person company supplies a variety of reclaimed-wood products to hundreds of clients worldwide, including the clothing company Patagonia, which uses it in its retail stores.

Growing on the High Line are more than 100,000 plants of 335 different species, many of which evoke the wild flora that flourished on the railway during decades of disuse. The Plant Group, a wholesale nursery in Franklin, Connecticut, supplied the park's perennials and ornamental grasses, including the moor grass shown here. CEO Ira Feinberg founded the company in 1986. Now, it has 20 to 90 employees, depending on the season, and 850 clients in the Northeast, including the Home Depot.

Irrigation System
Constructed in the 1930s as an elevated railway, the High Line was saved from demolition and converted to a public park in 2009. Plants and trees throughout the park are watered via an automatic drip irrigation system developed by Northern Designs of North Haven, Connecticut. The system uses more than 26,000 feet of tubing that allows water to drip slowly and reach plant roots. Founded in 1987 by Michael Astram, Northern Designs has five employees, $350,000 in annual revenue, and dozens of clients in the Northeast, including the National September 11th Memorial in New York City.