There will be a few tough days, but it's worth all the sweat and tears once you watch the sunrise at Machu Picchu's Gateway of the Sun. It's a pretty apt name.
Amazon & Incas
Cusco & Inca Trail with Galapagos
Cusco & the Inca Trail
Ecuador, Peru & Bolivia
Galapagos & Conquitasdor Adventure
Galapagos with Amazon & Incas