The Chancel has early Gothic style quadripartite rib vaulting (by Scott); five lancets in E wall, and early C20 reredos (by Caroe, 1937). To sides, groups of lancets deeply set, flanked by clusters of slim shafts. To S, triple sedilia and piscina; to N, worn late medieval relief. To N and S, elaborate arches to side chapels. The Harvard Chapel, to N, has fine SE doorway with ball-flower work, foliage-cresting to hood and flanking pinnacles; C14 tomb of Walter & Christine Aubrey. To S of chancel, the sacristy (rebuilt C19) has 3 east lancets, and double piscina; and the early C20 St Lawrence's Chapel has a re-used C13 E window, and C20 vaulting and elaborate doorways matching that of Harvard Chapel. The crossing is defined by four C13 arches; the piers to W arch retain wall paintings of an eagle, and an ermine-lined mantle. The stalls are by Scott. The area to W of the crossing was the site of the "Golden Rood"; stairs and upper level doorways to N and S. The N transept has two early C13 arches to Harvard Chapel. The S transept is similar. The nave arcade is supported on octagonal columns; roof restored by Scott, but essentially C16/C17; roof of N aisle possibly medieval. In the E end of the N aisle the former guild Chapel of the Corvizors is now dedicated to St Keyne. The chapel is enclosed by wooden screens, that to S a relocated late medieval screen; that to W a copy by Robert Thompson (his mouse signature located on an upright). Fine mid C14 tomb recess with ball-flower work and effigy, and inserted contemporary dormer window above. The cathedral has stained glass by Clayton and Bell in S lancets of chancel, and by Horace Wilkinson in Harvard Chapel. There are fine funerary monuments from C16 to C20 including, in N transept, that of Rev Thomas Watkins (died 1829); that of George Price Watkins (died 1843), and Sophia Watkins (died 1851), by I E Thomas. In S transept including that of William Morgan James, and Rev Thomas James (died 1798 and 1812 respectively) by Flaxman; that of Walter Jeffreys (died 1748) by Thomas Paty, and John Price (died 1719) by same artist. Also in S transept, the bronze effigy of Bishop Edward Bevan (died 1934) by W Goscombe John. Near Chapel of St Keyne is mid-C16 wooden female effigy from Games tomb. In N aisle, early C17 stone monument with alabaster effigies of Sir David Williams and wife of Gwernyfed, Felindre.
The Romanesque font of circa 1130-50 is stylistically linked to Hereford school of sculptors, and has a large bowl with Latin inscription on rim, and reliefs of fantastic birds and beasts. The polygonal wooden pulpit re-uses parts of C15 screen.