Pennsylvania
Pennsylvania shares the longest border.
New York
Pennsylvania borders Maryland to the south.
The state that touches the northern border of Pennsylvania is New York. It shares a long border with Pennsylvania, extending from the western part of the state to the northeastern region. This border includes various geographic features, including rivers and forests.
North Dakota and Idaho share a land border with Canada. Pennsylvania shares a maritime border with Canada across Lake Erie.
pennsylvania,new jersey,and connecticut
Maine, it shares a border with Vermont.
Delaware shares a border with Pennsylvania and with Maryland.
Connecticut is north of New York's maritime border
There is no Australian state which shares a border with all other states. No state except for Victoria shares a land border with Tasmania. South Australia shares a border with all mainland states and the Northern Territory.
Oklahoma shares most of Texas's northern border.