21 Grams|Belvedere Boulevard and Grace-St. Luke's — The pool where two strangers keep swimming

The pool sequence is small and strange: two people who have no business being in the same room, a gymnasium that smells of chlorine, water throwing light across the ceiling. It was shot at Grace-St. Luke's on South Belvedere Boulevard, in Midtown Memphis.

The church came first, a Gothic Revival mass of stone at Peabody and Belvedere built for a congregation formed when two older Memphis parishes merged. The school grew up beside it, and its buildings now run along Belvedere behind hedges and iron railing. The school is private and in session most of the year, so the pool itself is not somewhere a visitor goes, and it should not be.

Belvedere is the thing to see in any case. It runs south from Poplar through Central Gardens with a planted median down the middle and a row of houses that Memphis cotton money put up between 1900 and 1925 — Colonial Revival, Tudor, foursquare, one after another, under a tree canopy that has never been broken.

Walk it from Peabody down to Central in the late afternoon. The church tower stays in view over the roofline most of the way. Of everything Iñárritu filmed in this city, this is the stretch that still looks exactly like itself.