You'd probably classify vessels, docks and contracts with a marine flavor under a maritime heading, correct? Under certain circumstances, the federal court system might disagree.
There are some exceptions to what falls under a court's admiralty jurisdiction. I'm probably preaching to the choir, but you can't simply walk into a federal court and file any old lawsuit. To pry open the hatch and file a lawsuit in federal court, you need a jurisdictional basis.
There are several ways to navigate into the civil side of the federal court system. One is when your claim arises under the court's admiralty jurisdiction. Most times, if it has to do with a vessel or something salty, I'm already thinking federal jurisdiction. However, that's not always the case.
Take for example, a contract to build a vessel. While you may think it would be sufficiently maritime in nature for you to saunter into federal court, case law holds that admiralty law does not govern a construction contract. On the other hand, an agreement to repair a ship likely falls within the court's admiralty jurisdiction. But here's where it can be confusing. A contract to repair a dead ship (a vessel withdrawn from navigation) is not governed by admiralty law.
Accidents on piers have also been held to not be governed by admiralty law under the theory that piers are merely land extensions. Some decisions have also excluded man-made islands from the admiralty law. One court held that there's no admiralty jurisdiction to enforce a lien against a vessel under a contract where the amount being sought was largely for non-maritime related services.
Nowadays, in order to find admiralty jurisdiction, the court will generally consider whether the alleged tort occurred on navigable waters and whether there's a relationship between the wrongful act and a traditional maritime activity. Interestingly, a court may find admiralty jurisdiction where an accident occurs on navigable waters, even though the underlying negligent act occurred on land.
It's probably worth remembering that just because it sounds nautical doesn't mean you'll have admiralty jurisdiction.