Look up! In this building's original steeple, sexton Robert Newman hung two lanterns on the night of April 18, 1775, to signal Paul Revere that British troops were setting out for Lexington and Concord in boats across the Charles River, not on foot. We know that part of the story in Longfellow's words: “One if by land, and two if by sea.”

Officially named Christ Church, this is the oldest church building in Boston (1723). The design is in the style of Sir Christopher Wren. The 190-foot spire, long a reference point for sailors, appears on navigational charts to this day.

Members of the Revere family attended this church; their plaque is on pew 54. Famous visitors have included presidents James Monroe, Theodore Roosevelt, Calvin Coolidge, Franklin D. Roosevelt, and Gerald R. Ford; and Queen Elizabeth II. Markers and plaques appear throughout; note the bust of George Washington, reputedly the first memorial to the first president. The gardens ★ on the north side of the church (dotted with more plaques) are open to the public. On the south side of the church, volunteers maintain an 18th-century garden.

Free presentations that introduce the self-guided tour begin periodically during open hours year-round. For a more complete look at the church, take a Behind the Scenes tour ($8 adults, $6 seniors and students, $5 children 11 and under). The tour includes visits to the steeple and the crypt. It’s offered on weekends in March, daily from April through December, and the rest of the year by appointment. Tickets are available in the gift shop.

To continue on the Freedom Trail: Cross Salem Street onto Hull Street and walk uphill toward Copp’s Hill Burying Ground. On the left you’ll pass 44 Hull St., a fine example of the phenomenon known as the “spite house,” which is built to annoy neighbors by cutting off a view, for instance. The 10-foot-wide house is the narrowest in Boston.