State Tripoints: Two Down, One To Go [Update: Three Down, One To Go]

[Note: because I'm so cool I now also have the Austria-Slovakia-Hungary tripoint - see here. Oh you think that's an obscure tripoint? Probably because you don't have it, as a result of not being as cool as me. But hey. That's alright. Not many people are.]

There are many state tripoints, but a) I only care about the ones around Pennsylvania and California (seven) and b) even of those seven, four of them are in water.

The ones that are in the water are:

California-Arizona-Nevada (Colorado River)
Pennsylvania-New Jersey-New York (Delaware River)
Pennsylvania-West Virginia-Ohio (Ohio River)
Pennsylvania-New York-Canada (Lake Erie)


Of the remaining three, I've made it to two of them:

Pennsylvania-Maryland-West Virginia (done October 2016)
Pennsylvania-Maryland-Delaware (done December 2016)
California-Oregon-Nevada [edit: done June 2024]

Since I've been to the two tripoints including PA and MD, that means I've been to both ends of the Mason-Dixon line. According to noted geography expert my wife, that has only been accomplished by two other people in history: Mason, and Dixon. So now you have to call it the Mason-Dixon-MDK10 line. (I'm a humble man so I volunteer to make my name last.)

[Edit: Pennsylvania-New York-New Jersey, goddammit is on land. ONE MORE as of June 2024.]


PA-MD-WV:



PA-MD-DE:



[Added later due to coolness] Austria-Slovakia-Hungary