The New Cathedral of Salamanca (Catedral Nueva) adjoins the Old Cathedral of Salamanca (Catedral Vieja).
You can enter and buy a ticket for both at the Old Cathedral. You can also do a self guided rooftop tour of the cathedrals, which takes you through the Old Cathedral and takes you to the top of the building where you will be met with beautiful views of Salamanca.
The New Cathedral of Salamanca was constructed between the 16th and 18th century. It follows two styles: late Gothic and Baroque.
You can walk around both cathedrals and admire their craftsmanship for free.
In summer you can sit outside on benches and grassy areas. Alternatively cross the Roman Bridge and sit in the small park area there. It has one of the cities best views of the cathedrals.