On 9.7.13 you can claim the spot in the middle, then in Real Estate Desk move the plots to either one to just have one. On 10 combining isn't possible iirc.
Ah, I see, you didn't mention you cannot claim in the road district - then no, you cannot merge them, they need to be connected. Could also ask government if claiming would be fine, typically the protections are done via district-applying laws as well, so claiming wouldn't be too much of a problem, though on WT we wouldn't do it for security reasons.
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