Walk in NYC # 14, from Hamilton Heights to Morningside Heights
This self-guided tour is about 4 miles long and explores the western part of Harlem in detail so you will need at least 4-5 hours if you want to see and visit everything.
You will see historic houses and monuments, two renowned universities, contemporary art galleries, impressive churches and unusual museums; you will also walk along the Hudson River where, in season, you can eat on a former warship.
It is off the beaten track but has many surprising places; however, check beforehand that their opening hours are compatible with each other and your pace otherwise you will have to come back.
NB: if you have not already done so on another site, you can read the philosophy and general content of this itinerary by opening the “About the walks” link above or below.