Although not all the pieces of art that, due to the faith and affection of the parishioners towards their parish, have accumulated in the temple over the centuries, have come down to us, the creation of the Museum was still essential, since there are pieces of the highest quality. quality. The chapels of the Herreras and the next one of San Ildefonso, communicated as they are today, were certainly a wonderful setting for it, although it would be necessary to have at least double space for showcases, sacred ornaments and other objects.
First of all it was necessary to make air chambers in the walls to avoid humidity, due electric lighting, alarm system, etc.
After intense work, the Museum was happily inaugurated on February 2, 1985. The Adelantado de Segovia, the radio and other social communication media published reports of its inauguration, which was presided over by the Hon. Mr. Bishop of the Diocese.

The most outstanding pieces are the following:
Gilt rococo style console and good carving. On it is an Immaculate Conception, of the Renaissance type, well shaped and of the Castilian school. It is from the end of the 17th century and restored at the end of the 18th century. It had its crown and aureole of a plant that today is in a showcase of the Museum. This image was from the Archpriest's Foundation
Solis. 
 

Reliquary Christ from the 16th century, placed on a glass cabinet with a golden frame, inside covered with red cloth. The inscription goes: "In the year 1892 it was given as a gift by Josefa Prieto Fer. nández, Ángela, Enrique, Lorenzo and Silvia Duque, baptized in this church.

Canvas from the 17th century representing the Virgin with the dead Jesus Christ, medium execution. On the back it bears the inscription: "Diole Iglesia del Campo"

Canvas from the 17th century, representing the recumbent Christ, of medium execution.

Beautiful sculptural group of the Virgin with the Child and Santa Ana. It is a Flemish work from the end of the 15th century. The Virgin and Santa Ana appear standing, instead of sitting as usual, and Santa Ana offers the Child a flower in a bud. This group, which is a very important piece, was from the main Gothic altarpiece that the temple had before the current one.

Beautiful Hispano-Flemish carving from the 15th century, closely related to Burgos Gothic. It preserves its excellent primitive stew.
It represents the Virgin with the Child in the left hand. She is known among the people by the name of the "Blond Virgin", for having golden hair, as does the Child. It is a very valuable piece and, like the previous sculpture, it was from the primitive main altarpiece.
Valuable Gothic table, the work of the Segovian workshop of the 15th century.
It represents the imposition of the chasuble on San Ildefonso by the Virgin. It bears signs: "You will be my Chaplain", which the Virgin said to the Saint. Until a few years ago this table was in its original location, next to the side door of the temple. Below was the inscription, now almost lost: "This altar was ordered by A. Diaz de Villarroel, in honor of S. Alifonso, finished in the year 1470». In the painting also appear San Francisco and the portrait of the donor, the Racionero Villarroel.

Carving of the Immaculate Conception, neoclassical, early 19th century, good execution and angels on the base. It was repainted in 1853 by José de Mora in the amount of 380 reales and the golden base by Rosendo Aguilar in the amount of 60 reales.

Valuable Flemish triptych by Adrián Rembrandt. In its center it bears the Crucifixion, with the three Marys and Nicodemus. The Virgin and Saint John are represented on the side tables. The landscape in the background is very rich, with multiple figures, and the city of Jerusalem. The doors have the Annunciation, in grisaille. It was brought from Flanders in the 16th century by Don Alonso Moreno to be placed in his chapel of San Ildefonso.

Canvas from the 17th century, representing Saint Cosme and Saint Damien. It has a Renaissance-style architectural background and the figures of the Saints are dressed in bonnets with white tassels and costumes from the time when the painting was executed. One carries a book and another a medicine chest. In the background is a sick person's bed under a canopy. It is of medium execution and was originally in the southern arm of the temple transept.
Two reliquary busts of San Marcos and San Lorenzo, from the 17th century, of good execution.

Beautiful carving of San Matías, 16th century, with gothic overtones, and preserves the original painting.

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