The cathedral is in a cruciform shape symbolizing the crucifixion and resurrection of Jesus Christ. 

The central nave is much wider than the double aisles flanking its sides.

At the cruciform’s crossing lies an octagonal altar in whose center is the white marbled Alta Mayor. It is here where daily mass is celebrated and other important services are performed. Smaller services are usually held elsewhere in the basilica, notably at the Altar of the Sacred Heart of Jesus.
Please face south while standing slightly left of center relative to the Alta Mayor. Look up and you will notice a heart-shaped window in the upper reaches of the cathedral.

Peering through the window is the statue of Our Lady of Quito atop El Panecillo behind the cathedral.

This line of sight symbolizes the spiritual connection between the Virgin of El Panecillo, and this cathedral dedicated to the Sacred Heart of Jesus.
 
Now, please turn around and face north. Look up at the balcony above the chapel at the north end of the cathedral. This is where the image of the Sacred Heart of Jesus is housed. 

Painted by the Ecuadorian painter Rafael Salas, this same painting was used during the 1874 consecration ceremony after which Ecuador became the first to consecrate its entire nation to the Sacred Heart. This painting is said to have inspired the construction of this cathedral.
 
The first floor of the cathedral features 48 stained-glass windows depicting Catholic doctrine and scenes from the Bible.

As they visually narrate biblical stories, the windows are often collectively referred to as the “glass Bible.”

The windows also depict religious figures from the history of Christianity in Ecuador as well as numerous roses arranged in ornate rosettes.
Below the balcony and at the very front of the central aisle nestled against a magnificent white marble wall, there stands a heart-shaped tabernacle housing the blessed sacrament. 

On this marble wall, the declaration of consecration to the sacred heart is inscribed in gold letters.

Along the aisles of the cathedral, there are 24 side chapels. Each represent one of Ecuador’s 24 provinces by bearing its flag, coat of arms and patron saint. Intertwining nation and church, the cathedral thereby symbolizes national unity.

Above the aisles, you will see two choir balconies. These are ceremonial spaces for Ecuadorian dignitaries and the diplomatic corps.

Now, take a leisurely stroll down the nave. 

There are 24 columns along each side aisle above which there are 15 bronze statues.

These statues depict the twelve apostles and three gospel writers as follows:
Facing north relative to the altar of the Sacred Heart, 

To the left are Saint Peter, Saint Andrew, Saint John, gospel writer Saint Matthew, Saint Simon, Saint Jude Thaddeus as well as gospel writers, Saint Mark and Saint Luke.

To the right are Saint Paul, Saint James the Great (son of Zebedee), Saint Philip, Saint Bartholomew, Saint Thomas, Saint James the Less (son of Alphaeus) and Saint Matthias.

For those wishing to visit the Sacred Heart of Mary Chapel, please proceed to the back of the altar of the Sacred Heart of Jesus and scan QR code number 3 attached to the wall at the left of the entrance to the Chapel.

For those who would like to learn more about the cathedral's exterior, please exit through the south entrance and scan QR code number 4 attached to the exterior wall. If you exit facing El Panecillo Hill, you will easily find the south entrance.