One of the best tours in Belfast is free. At 11am and 2pm Monday to Friday there is a free tour of the Parliament Buildings at Stormont. The buildings date back to 1923 and is steeped in the colourful political history of Nothern Ireland. The best way of getting there is the CitySightseeing Belfast hop on hop off bus that runs from the city centre every 30 minutes.
The small cafe there is also a great place to get a tea or coffee with a scone, the cheapest you will find in Belfast too.
Get back to nature on a day trip to Plitvice Lakes National Park from Zagreb and go for beautiful walks in the forest reserve. Marvel at the 16 terraced lakes and numerous waterfalls from the walkways that wind around and across the water.