The neighbor's land, the holder of the easement, benefits by having beach access through your land. For example, allowing the utility company to come on your land to lay a gas line. The utility company, the holder of the easement, benefits by having use of the land to lay the gas line. A negative easement prohibits a lawful use of land - for example, creating a restriction on the type and amount of development on land. A covenant is a promise that certain actions have been taken, will be taken, or may not be taken.
Covenants can bind subsequent owners of the land.
There are special legal requirements needed to bind subsequent owners. A reversionary interest places a condition on the transferee's right to own and occupy the land. If the condition is violated, the property is returned to the original owner or the owner's successors. Each owner in the chain of title must comply with conditions placed on the property. If a condition is violated the property can revert to the original owner, even if there have been several transfers in the chain of title.