I enjoy a variety of tours while on vacation. A few of my favorites are hop on, hop off tours, which are offered in many larger cities. They are buses that travel a specific loop with several items of interest on the way. Riders can hop on and travel until the bus stops at a site that interests them. When they are done, they hop back on and do it again until they have seen all of the sites on the route.
My boyfriend introduced me to the hop on hop off tour when we visited New Zealand several years ago, as his brother lives there.