We first went into the Parliament building but didn't plan to well and missed the tour we wanted to take. They run them frequently but we didn't want to wait so we took a quick walk around the main floor and learned a bit about how the Scottish government works. So if your interested in the tour make sure you check the site for times.
The Palace of Holyroodhouse is near the Parliament and at the end of the Royal Mile. I was so excited to visit here and it's obviously very popular. The line for tickets was long but it moved fairly quickly and we purchased the Royal Visit tickets so we got a guided garden tour, entrance to the Queen's Gallery, and entrance to the palace itself which is self guided but has an audio guide available for the rooms open to the public. I loved the garden tour as we were able to go off the path and deep into the gardens with our guide.