The Leaning Tower and much, much more...
Their blooming wreaths from fair Valclusa's bowers
To Arno's myrtle border.
(Mark Akenside, Pleasures of the Imagination)
Pisa is famous worldwide for the beautiful monuments in the Field of Miracles, the best known of which is the Leaning Tower, one of the 7 wonders of the world, which has become the symbol of the city.
Besides being a beautiful city to explore and enjoy slowly, Pisa is also an excellent base to explore Northern Tuscany. Pisa's "Galileo Galilei" airport offers a large number of international and national flights operated by national airlines and low-cost airlines, which allow tourists to fly to Pisa at very reasonable prices.
Pisa has a very conveniently located railway station which is a crucial stop along the Tyrrhenic coastal railway line and which offers very easy access to beautiful cities, like Florence and Lucca.
For these reasons, a car is not absolutely necessary. However, if you come by car or decide to rent one, Pisa is an excellent base to explore western, northern and central Tuscany.