Turn on relay shield wemos d1 mini

Projects Programming
1

I am trying something very simple, turning on and of a relay shield that is mounted on my wemos d1 mini.
Can someone please point out what it is I am missing here?

const int relayPin = D3;

void setup()
{
  pinMode(relayPin, OUTPUT);
}

void loop()
{
  digitalWrite(relayPin, HIGH);     
  delay(1000);                  
  digitalWrite(relayPin, LOW);       
  delay(1000);            
}
2

The relay on my relay shield is on pin D1 and it is marked as such on the bottom of the shield. Are there any markings on yours ?

3

I am such an idiot... D1 it is!
No obvious markings.

Thanks a lot, have been banging my head for a while!