PALAEOCHRISTIAN BAPTISTERY, C5-C7. SAN MARCELLO AL CORSO This extraordinarily well-preserved baptistery was discovered in 1912 during works under the adjacent palazzo Salviati Mellini. It was once in a separate building attached to the late-C4 church of S. Marcello, whose orientation was opposite to today's, as the lower stretch of the Corso had become swampy, so part of the urban section of the via Salaria, now via di S. Marcello, higher up the base of the Quirinal, supplanted the Corso (via Lata) for several blocks. The baptistery shows two different brick layers, the lower from the early 400s,the upper from 200 years later but clearly on an identical plan. The simple white marble revetment, probably reused from the C5 baptistery, is incised with plain lines to create frames. The octagonal form has four semicircular niches, one in every second wall, and the water comes from a natural spring that still wells up inside the rectangular gap in the floor of the baptistery, and once filled the octagon up to at least knee height.
I went into the Six Senses hotel in palazzo Salviati Mellini and asked if they would let me see the #palaeochristian #baptistery of #SanMarcello, over which the palazzo is built, and they showed me this marvel, surely the best-preserved example from #LateAntiquity in #Rome.
