Summiteers see few sights. What with arms control negotiations in the morning and state dinners at night, the Gorbachevs might never see the real Washington. In the interest of world peace, Post readers are suggesting stops on a highly unofficial tour of the area's lesser-known charms.

Today's guide: Marie Quinlan, senior researcher at the National Endowment for Long Term Health Care.

Destination: The 12:30 mass at St. Augustine's Church, 15th and V streets NW.

"It's the oldest black Catholic Church in the District and the mass is like an old-fashioned high mass. All the responses are sung, but it's in a gospel idiom. And the people really praise the Lord. They sway and they move and they come rocking down the aisle. They move and they move you. They have brass and piano and drums. And they have 65 voices in the choir. It's a more spiritual experience than a regular mass. It's enlivened by the music.

"The place is always packed, five- or six hundred people, and it's such a rich community. During they mass they always introduce new people.

"The priest says, 'Who's new today?' And everybody welcomes you by applauding. It's extraordinary. And they have a pool in the back of the church for baptism by immersion.