Nice, France

My girlfriend and I just finished cycle touring from Munich to Nice (beautiful areas!). We made better time than expected, and have some time until flying out from Nice on August 1st. Any recommendations on a week-long loop (500-800km) we could do from here? We came down from Grenoble through Sisteron,, so would prefer not to go back that way... Maybe something on the Italian side of the mountains? Alternatively, any recommendations on things to see, hikes/day rides to do, or short term work/volunteer opportunities here in Nice? Thanks,
Anders