1. The Stockholm Parliament House, also known as Riksdagshuset, is the home of the Swedish Parliament, the Riksdag. It is located on the island of Helgeandsholmen in central Stockholm, next to the Royal Palace.

The building itself is an architectural masterpiece and is often regarded as one of the most beautiful parliamentary buildings in the world. It was designed by architect Aron Johansson and was completed in 1905. The exterior of the building is made of red brick and features a mix of architectural styles, including neoclassical and gothic influences.

Inside the Parliament House, visitors can explore the various chambers and halls where parliamentary sessions and debates take place. One of the highlights is the chamber of the Riksdag, which is adorned with beautiful artwork and features a glass ceiling that allows natural light to filter in.

2. The Stockholm Parliament House is open to visitors on weekdays. The exact opening hours may vary, so it is recommended to check the official website or contact the visitor center for the most up-to-date information. The visitor center can be reached at +46 8 786 40 00.

3. Admission to the Stockholm Parliament House is free of charge. However, visitors are required to book a guided tour in advance. Tours can be booked online through the official Riksdag website. The address of the Parliament House is Riksgatan 3, 100 12 Stockholm.

Transportation options to the Parliament House include public transportation such as buses and subway. The closest subway station is Gamla Stan T-bana, and various bus lines also stop nearby. It is also possible to reach the Parliament House by walking from central Stockholm, as it is located in close proximity to major tourist attractions.