National Center for Supercomputing Applications (NCSA)

The NCSA is one of the most historically significant buildings in the history of computing, and almost no one who walks past it knows it. This is where the graphical World Wide Web was essentially born: in 1993, the Mosaic browser was developed here by a student team led by Marc Andreessen, making the internet visually navigable for the first time and setting off the web's transformation into a global medium.

The building is not a museum and is not generally open for public tours — it is a working research centre. But the exterior plaque and the area around the building are worth a stop for anyone interested in the history of technology. The NCSA continues to operate as one of the leading supercomputing facilities in the United States, and the Blue Waters supercomputer operated here until 2022 was among the most powerful civilian machines in the world.

things to do sight
A story
In 1993, a team of undergraduate students and graduate researchers at NCSA released Mosaic — the first web browser with a graphical interface that could display images inline with text. Until Mosaic, the internet was largely text and commands. Within two years of its release, it had changed how most of the world understood the internet. One of the students on the team, Marc Andreessen, went on to co-found Netscape. The Mosaic source code was written in this building.