Build on an empty connected edge
A paid road costs one wood and one brick. The edge must be empty and connect to your own building or to an unoccupied corner already touched by your road network. You cannot place a road on top of another player’s road.
Your opening road is different: it must sit beside the settlement you just placed in setup. A free road from a development card still follows normal connection rules; free means no resource payment, not unrestricted placement.
An opponent’s building closes the crossing
You cannot extend your network through an opponent’s settlement or city. Their building occupies the junction your road would need to use. Your existing road pieces stay on the board, but they do not grant passage through that occupied corner.
This matters before an opponent settles too. A gap along your route may be a legal settlement site for them if their own road reaches it. Consider whether that corner is a vulnerability before investing in a long chain.
Branches are options, not automatically extra length
The total number of road pieces you own is not your Longest Road length. The award uses your longest continuous walk without reusing an edge. At a fork, a single route cannot count all branches if doing so requires travelling over the same road again.
A branch can still be strategically useful because it reaches a resource or port. Judge that utility separately from the award. The road counter and award announcement help distinguish expansion from an actual scoring change.
Name the destination before paying
Ask what another road achieves: a settlement site, a port, a protected junction or a longer qualifying route. If the answer is only “I have spare wood”, consider whether keeping the cards for a trade would be more useful.
Each player has 15 road pieces. Even with enough resources, a route is constrained by legal edges, opponents and your remaining pieces. Recheck the board after every other player’s turn rather than treating your first plan as a reservation.