Although the municipality of Melgaço covers a wide area (238,1km2 or 91, 9 square miles approximately) the main town – “Vila” is a small place.
Walking is the best way to explore Vila and I think I don’t need to recommend you a specific path. You’ll find multiple services like the Post Office, cafes and stores as you would expect from any small town. It’s also safe so if you want to go out for your explorations at 4a.m you won’t have any problem. Please check the map i’ve created in Google for orientation: HERE.
Some tips to guide your walk:
There are two squares in Vila: “Largo Hermenegildo Solheiro” where the TownHall is located and near the Firefighter’s HQ; “Praça da Republica” where you can visit small underground ruins and there’s also a free Internet Center.
You should also walk along the “Rio do Porto” Urban Park (blue line) along a small river to find a playground for kids, a small half-pipe (and an area for skaters to master their tricks) and a bar (called Rio’s) behind the City Hall.
In the Old Town zone, streets are smaller and maybe more confusing. If you follow “Rua Direita” which pretty much is the main-broader-street there you should have no problem finding the entrance to the Castle, “Solar do Alvarinho” (– the building dedicated to the Alvarinho Wine), the “Matriz” Church and the Cinema Museum. The Castle Gardens are also nearby of course.