Looks like a short walk
https://www.google.com/maps/dir/Ocean+Gateway+Pier,+Portland,+ME+04101,+USA/Maine+Narrow+Gauge+Railroad,+Thames+Street,+Portland,+ME,+USA/@43.6600087,-70.2489261,17z/data=!3m1!4b1!4m14!4m13!1m5!1m1!1s0x4cb29c412d5974b1:0xe03a90ca551555f3!2m2!1d-70.2459649!2d43.6592415!1m5!1m1!1s0x4cb29c4389434423:0x51ce47f13de64d19!2m2!1d-70.2457198!2d43.6607543!3e2?entry=ttu