A highlight of any visit to Salamanca is its famous university.

The oldest in Spain, it was established in the early 1200s and was one of Europe’s leading centers of learning for 400 years. Today, while no longer so prestigious, it’s laden with history and especially popular with American students for its excellent summer program.

The university’s ornately-decorated grand entrance is another example of Spain’s fancy Plateresque style. The people studying the facade aren’t art fans. They’re trying to find a tiny frog on a skull that students looked to for good luck. Okay, up the column, take a left, find the skull. The frog’s on top.

Now forget him. Let’s follow the facade’s symbolic meaning: The bottom part thanks King Ferdinand and Queen Isabel for the money to make the building. The middle section celebrates Charles V with the coat of arms of his Habsburg Empire — the world’s only superpower in the early 1500s. Finally, as a statement of the school’s open mindedness, the top honors the Pope while putting him in the company of pagan gods.

This venerable arcade leads to lecture halls where Spain’s brightest minds grappled with issues raised by the dawning of a new age. Imagine Golden Age heroes paging through these books and pondering these globes. Cortés came here for travel tips.

The narrow wooden tables and benches — whittled down by centuries of studious doodling — are originals. Professors spoke boldly from the pulpit.

It was here that the free-thinking monk Luis de León taught in the 1500s. He challenged the Church’s control of the word of God by translating part of the Bible from Latin into the people’s language of Castilian. Because of this, he was tossed into jail for five years. When finally released, he returned to this pulpit and began his first lecture with, “As we were saying…”

Courageous men of truth like Luis de León believed the forces of the Inquisition were not even worth acknowledging.

Traditionally, Salamanca’s struggling students earned money to fund their education by singing in the streets. This centuries-old troubadour tradition survives today as musical combos — called tuna bands — dressed in distinctive outfits, play lutes, guitars, and sing. For a fee, they serenade fancy family gatherings. And, celebrating with a beer after their gig’s done, they can’t resist brightening a bride-to-be’s bachelorette party. And this fun-loving tuna band — the oldest in Salamanca — gave us a memorable trip finale back on the Plaza Mayor.