Just like the capital of basically any country in the world, Ottawa has more free attractions than other cities in the same nation. Although it does not reach the level of Washington D.C. where every freaking awesome thing is free, Ottawa still has much to offer on-budget travelers.
Parliament building – Central block guided tour
This is a must-do for anyone who comes to Ottawa. The tour is actually not impressive at all. There is not much about the government – House of Commons and Senate – that you can learn during the tour. The fun part is that you could walk in the working building of the Canadian government. The architecture of the building is amazing. The library is probably the most beautiful room in the whole country. The visit to Peace Tower, from which you can view the whole city by the river from high above, is also included in the tour. Besides, for girls, the tour guides are usually strikingly good looking.
If you love nature, Gatineau Park is a perfect destination. Just across the Ottawa River from Parliament Hill, the park offers a scenic stay away from the city. Best visited during fall, when the symbolic maple leaves all turn red/orange.
Located on the ground floor of the Bank of Canada and free, the museum has a collection of coins and bills throughout history in various regions. My favorite part is the videos about counterfeiting bills and the war against them.
Basilica Notre Dame
Right next to the National Gallery of Art, the church is the oldest and largest church in Ottawa, pretty much the same in interior design as the one in Montreal.
Simply walk along the Rideau canal and/or Ottawa river
On a summer afternoon, in the sunset, this walk is the most rewarding activity that I could expect in the peaceful and gorgeous city of Ottawa.
Visit Royal Canadian Mint boutique
A tour of the Mint costs money, but only visiting the boutique is free. The boutique is home for some collector coins and also one 28-pound gold bar. Taking a picture with this gold bar is definitely some souvenir to bring home.