Contiguous
adjective
connecting without a break; within a common boundary
“the 48 conterminous states”
Similar: conterminous
adjective
having a common boundary or edge; abutting; touching
“Rhode Island has two bordering states; Massachusetts and Conncecticut”
Similar: adjacent, conterminous, neighboring
adjective
very close or connected in space or time
“contiguous events”
Similar: immediate