San Crisogono in Trastevere is dedicated to the martyr Saint Chrysogonus. It was probably built in the 4th century under Pope Silvester I (314–335), rebuilt in the 12th century by John of Crema, and again by Giovanni Battista Soria, funded by Scipione Borghese, in the early 17th century.
The bell tower dates from the 12th century rebuilding. The interior of the church was rebuilt in the 1620s on the site of a 12th-century church. The 22 granite columns in the nave are reused antique columns. The floor is cosmatesque mosaic, but most of it is hidden by the pews. The confessio in the sanctuary area is from the 8th century. The high altar is from 1127, with a baldachino from (1627 or 1641) by G.B Soria.
Remains from the first church, possibly from the reign of Constantine I, and earlier Roman houses can be seen in the lower parts, reached by a staircase in the sacristy. The ruins are confusing, but you can easily find the apse of the old church and you can see the remains of the martyr's shrine in middle of the apse wall. The church had an uncommon form; rather than the normal basilical plan with a central nave and two aisles on the sides, it had a single nave.
The paintings are from the 8th to the 11th century, and include Pope Sylvester Capturing the Dragon, St Pantaleon Healing the Blind Man, St Benedict Healing the Leper and The Rescue of St Placid.
Several sarcophagi have been preserved here, some beautifully decorated.
References:The Jan Hus Memorial stands at one end of Old Town Square. The huge monument depicts victorious Hussite warriors and Protestants who were forced into exile 200 years after Hus, and a young mother who symbolises national rebirth. The monument was so large that the sculptor designed and built his own villa and studio where the work could be carried out. It was unveiled in 1915 to commemorate the 500th anniversary of Jan Hus' martyrdom. The memorial was designed by Ladislav Šaloun and paid for solely by public donations.
Born in 1369, Hus became an influential religious thinker, philosopher, and reformer in Prague. He was a key predecessor to the Protestant movement of the sixteenth century. In his works he criticized religious moral decay of the Catholic Church. Accordingly, the Czech patriot Hus believed that mass should be given in the vernacular, or local language, rather than in Latin. He was inspired by the teachings of John Wycliffe.