From the front door Alcatraz doesn't look too forbidding. Because the entrance is up above the original level of the fortress and enters the prison at the second floor it almost looks a bit like a post office or other governmental building. Looking closer, you can find one of the indications of the American Indian Movement occupation of the island. The red stripes under the eagle have been modified to read "FREE".
In my mind the Indian occupation is perhaps more important than Alcatraz's days as a prison, but it doesn't capture the imagination of hollywood to the same extent as a prison break.