After we turn the corner at the hill top, with its fine view over the Palatine, and cross the trench of fortification formed during the fear of a Garibaldian invasion in 1867, we skirt what appears to be part of a city wall. This is in fact the wall of the Honorian city, built by Pope Honorius III., of the great family of Savelli, whose idea was to render the Aventine once more the populous and favourite portion of the city, and who began great works for this purpose. Before his arrangements were completed St. Dominic arrived in Rome, and was appointed master of the papal household, and abbot of the convent of Sta. Sabina, where his ministrations and popularity soon formed such an attraction, that the pope wisely abandoned his design of founding a new city which should commemorate himself, and left the field to St. Dominic,--to whom he made over the land on this side of the hill. Henceforward the convent of Sta. Sabina and its surroundings have become, more than any other spot, connected with the history of the Dominican Order,--there, all the great saints of the Order have received their first inspiration,--have resided,--or are buried; there St. Dominic himself received in a beatific vision the institution of the rosary; there he was ordered to plant the famous orange-tree, which, being then unknown in Rome, he brought from his native Spain as the only present which it was suitable for the gratitude of a poor monk to offer to his patron Honorius, who was himself one of the great botanists of his time,--an orange-tree which still lives, and which is firmly believed by the monks to flourish or fail with the fortunes of the Order, so that it has lately been greatly the worse for the suppression of the convents in Northern Italy, though the residence of Père Lacordaire within the convent proved exceedingly beneficial to it, and his visit even caused a new sucker to sprout. The _Church of Sta. Sabina_ was built on the site of the house of the saint--in which she suffered martyrdom under the Emperor Hadrian,[187] in A.D. 423--by Peter, a priest of Illyria, "rich for the poor, and poor for himself" _(pauperibus locuples, sibi pauper)_, as we read by the mosaic inscription inside the principal entrance. St. Gregory the Great read two of his homilies here. The church was rebuilt in 824, and restored and reconsecrated by Gregory IX. in 1238. Much of its interest,--ancient pavements, mosaics, &c.,--was destroyed in 1587 by Sixtus V., who took the credit of discovering the relics of the martyrs who are buried beneath the altar.