The Old North Church, a beacon for Paul Revere's famous warning of the movement of British forces, and a symbol of the American Revolution, has gone high-tech with the installation of light-emitting diodes, or LEDs.

The energy-efficient lights illuminate ceiling vaults inside the church, whose steeple was used to display two lanterns as a signal about British troop movements on April 18, 1775 — the night described in Henry Wadsworth Longfellow's famous poem, which included the line: "One if by land, and two if by sea."

LEDs haven't yet replaced the slightly less-modern compact fluorescents that the church began using two years ago in its modern versions of the steeple lanterns.

The 18 strips of LEDs inside church's sanctuary — replacements for old-fashioned incandescents — may seem an anachronism at the most visited historic site in a city with a rich Revolutionary War legacy. But the lights are tucked into crown molding, illuminating the graceful white ceiling arches while the lights themselves are hidden from direct view by tourists and worshippers below.