Washington's oldest church, St. Paul's Episcopal on Rock Creek Church Road NW, celebrated its 266th birthday last Sunday.

"How fitting that it should fall on Pentecost Sunday," the Rev. E. Pinkney Wroth Jr., told his proud congregation. "The Pentecost is though of as the birthday of the whole Cristian church, the day when the apostles were gathered in unity,"

Wroth spoke to an audience that included much of the 350-member congregation and members of the Daughters of the American Colonists, who presented a historic plaque commemorating the church and its churchyard, an 86-acre cemetery appear in the National Register of Historic Places.

"Rock Creek Church," as St. Paul's is popularly known, sits atop a rippling, kelly green hill two miles from Rock Creek, just off North Capitol Street near the Soldier's and Airmen's Home, which also has a cemetery.

The site of the church was determined in 1719 when a 100-acre plot was donated to the church, Wroth said this week.

Noting that no bridges existed then over major area rivers and that Rock Creek was on high ground and accessible, Wroth said: "Rock Creek was the only fordable stream during all parts of the year, so this site was chosen."

The present 86-acre site is the result of a 14-acre claim by the city government for the right-of-way for New Hampshire Avenue.

"Of course, a church is not a building but a group of people. We date back to the second Sunday of May 1712, because that is when regular meetings were established.

By around 1800, we had become pretty much a public institution," Wroth said.

Tombstones in the churchyard date to the early 1700s, and in later years, the rich and powerful. A drive along the curving roads reveals row after row of ornate mausoleums and memorials, many with breathtaking stained glass windows.

John Quincy Adams' grandson Henry is buried under a hillside grotto that contains a famous bronze statue he commissioned in his wife's memory by sculptor Augustus Saint-Gaudens. Writer Alexander Woollcott called the figure "the most beautiful thing ever fashioned by the hand of man on this continent."

Many people manage to view the statue of a hooded figure every year, despite instructions by the Adams family that no markers or signs be erected to aid the curious.

Asked how his congregation is affected by worshipping in the midst of a cemetery, Wroth said:

"It has made us more aware of death, more able to face death."

Wroth said most members of the congregation have picked their burial plot and tombstone. "Many of the tombstones are carved and in place, just waiting for the date of death to be filled in," he said.

Wroth , who resigned in 1960 as dean of the Episcopal cathedral in Havana, seems most at home pointing out the original church walls, the architecture and the artistic treasures.

Walking through a churchside glade with brown pine needles scattered at his feet, Wroth kicked at a 3-foot-wide stone, which he said was part of the original building of 1719.

A larger building was erected in 1775 and expanded in 1826. A fire damaged the interior in 1921. The present building include two brick walls left from the 1775 structure.

"The 1775 church began here," Wroth said, placing both feet inside the small, gleaming sanctuary and pointing to the 203-year-old side walls. "Those walls were build in colonial times. They are still standing and still in use today. That makes it the only colonial church left in Washington," he said.

"This is the mother church of Washington," he added.

To commemorate that distinction, Canon Charles S. Martin, headmaster emeritus of St. Albans School will speak at an 11 a.m. service May 23. Wroth was chaplain at St. Albans during 1950-53.

Wroth said he and others at the church enjoy showing visitors the church and cemetery The cemetery helps support the church, which is in excellent condition.

Rising near the entrance to the church is a 500-year-old tree known as the "Glebe Oak," a survivor of the original wooded area founded by the colonists. The magnificence of the huge tree is believed to have helped determine the site of the church.