Žižkov
In the afternoon of our second day in Prague, we rode the Metro. The public transportation system in Prague is awesome and super easy once you get the hang of it. Be aware: you need change for the ticket machines, or you can buy a ticket at a tobacco shop or ticket counter. The 24-hour ticket is a good deal, just validate once and go anywhere.
We visited the Karlin district, a newly gentrified and cool zone. From there, we walked through an insanely long pedestrian tunnel to Žižkov, which is where Sequoia lived ten years ago when she worked as an English teacher. She described Žižkov as "gritty," and indeed it was, but in a good way. Prague has changed significantly in the past ten years.
We loved walking around Žižkov, including all the way up a super steep hill to the National Monument on Vítkov.