A couple of years ago, I walked the entirety of Wilshire Boulevard, from One Wilshire in Downtown all the way to the beach in Santa Monica. It's about 16 miles, and it takes all day, but you can do it.
Breakfast at Eggslut, lunch at the Food Trucks at LACMA, and dinner in downtown Santa Monica.
Landmarks along the way include Downtown, Macarthur Park, Koreatown, LACMA, La Brea Tar Pits, Beverly Hills, Westwood, and of course Santa Monica.
It's a great way to re-experience the city.