Decline

The tough luck of Venice came from three different angles.

First, the Ottoman Empire took control of the Middle East in the 15th century, and trading with the Far East via land was increasingly difficult. On the other hand, Bartolomeu Dias reached the southern tip of Africa (which he called the Cape of Storms initially) and opened the sea route to Asia, while Christopher Columbus and Ferdinand Magellan opened up the gigantic market by heading west. Taken together, the halo of Venice the republic as a financial and commercial center faded. There is actually no reason to pay any attention to a small coastal city along the Adriatic Sea or those trivial islands of the Aegean Sea.

Venetians in the Middle Age were not stupid. They saw their difficulty rather plainly and did try to save their city by exploring new sources of income.

And they went for tourism.

PS. The thing that only goes up and never comes down is – our age.