The church of San Pablo consists of a nave and aisles of five bays, transepts and apsidal choir, with many added chapels. The nave groining bays are square, those of the aisle oblong, a mode of planning which marks rather an Italian-Gothic than a French or German origin. The church is vaulted throughout, with very domical vaults, and lighted with lancets in the aisles, circular windows in the clerestory, and traceried windows in the choir. Part of the old western gallery still remains. The vaulting has transverse, diagonal, and ridge ribs. The apse is well buttressed, but, like all the churches in Burgos, San Pablo has lost its old roofs, and has been so much spoilt by the additions which have been made to it, that its exterior is very unprepossessing. Not so the interior, which, both in scale and proportion, is very fine. The architect of San Pablo is said to have been Juan Rodriguez, who commenced it in 1415, and completed it before 1435.[60] Another convent, that of La Merced, has been treated in the same way, and is now a military hospital. Its church is on the same plan as that of San Pablo, with the principal doorway in the north wall instead of the west, and this opening under the usual vaulted gallery. There is, too, a small apsidal recess for an altar in the north wall of the north transept. The window tracery and details here are all of very late Pointed, but the buttresses and flying buttresses are good. Flat roofs, destroyed gables, and the entire absence of any steeple or turret to break the mass, make the exterior of little value. This convent was moved to its present site in A.D. 1272, but I doubt whether any part of the exterior now visible is so old as this. I saw no other churches worthy of mention in Burgos; but there are others which ought to be examined in the neighbourhood, among which one a little beyond Las Huelgas, of large size, surrounded by trees, and apparently belonging to a convent, seemed to be the most important.[61] There are but few remains of old Domestic Architecture. The Palace has been modernized, but is still approached by a groined passage from the south door of the cathedral. The Palace of the Constable Velasco is a bald and ugly erection of the sixteenth century, in the very latest kind of Gothic; its walls finished with a strange parapet of crocketed pinnacles and stones cut out into a sort of rude fork; its entrance a square-headed doorway, with a large space above it, enclosed with enormous chains carved in stone, within which are armorial bearings. The internal courtyard is surrounded by buildings of three stages in height, with open arcades to each, and traceried balconies. The arcades and windows throughout have debased three-centred arches.