1. The Piccolomini Library, also known as Libreria Piccolomini, is a beautiful library located in the town of Siena, Italy. It is part of the larger complex of the Siena Cathedral, also known as the Duomo di Siena. The library was commissioned by Pope Pius III in honor of his uncle, Pope Pius II (whose birth name was Enea Silvio Piccolomini), and was completed in 1504.

The library is renowned for its magnificent frescoes, which were painted by the artist Pinturicchio and his workshop. These frescoes depict scenes from the life of Pope Pius II and include vibrant colors and intricate details. The main fresco, located on the ceiling, is known as the \"Four Cardinal Virtues\" and represents Justice, Temperance, Prudence, and Fortitude.

In addition to the frescoes, the library houses a collection of beautiful illuminated manuscripts and books, many of which were commissioned by the Piccolomini family. The library also features an intricately carved wooden reading desk, which is adorned with ancient books and decorative elements.

2. The Piccolomini Library is open to the public and can be visited during the opening hours of the Siena Cathedral. The opening hours may vary depending on the season, so it is recommended to check the official website or contact the cathedral for the most up-to-date information. The phone number for the Siena Cathedral is +39 0577 286300.

3. The ticket for visiting the Siena Cathedral includes access to the Piccolomini Library. As of my knowledge (as of 2021), the ticket price for adults is around 10 euros. There may be discounted rates available for students, seniors, and children. The Siena Cathedral is located in the historical center of Siena and is easily accessible by foot or public transportation.