This is one of the most impressive 'fountains' you're likely to see anytime soon. The Captain Cook Memorial Jet can be found on Lake Burley Griffin, and you've got to witness it at least once.
The water coming out of the jet has an impressive velocity of 260kph, and can reach heights of up to 147m. It can be seen from spots all around the lake, but if you head to the National Capital Exhibition by Commonwealth Park you can head out to their special viewing platform.
The normal operating times of the jet are between 2pm and 4pm daily.