Public holidays
1644, Portugal, Sintra
| # | Date | Public holiday |
|---|---|---|
| 1 | Friday, 1 January 1644 | Ano Novo |
| 2 | Friday, 25 March 1644 | Sexta-Feira Santa |
| 3 | Monday, 25 April 1644 | Dia da Liberdade |
| 4 | Sunday, 1 May 1644 | Dia do Trabalhador |
| 5 | Thursday, 26 May 1644 | Corpo de Deus |
| 6 | Friday, 10 June 1644 | Dia de Portugal |
| 7 | Wednesday, 29 June 1644 | Dia de São Pedro |
| 8 | Monday, 15 August 1644 | Assunção |
| 9 | Wednesday, 5 October 1644 | Implantação República |
| 10 | Tuesday, 1 November 1644 | Todos os Santos |
| 11 | Thursday, 1 December 1644 | Independência |
| 12 | Thursday, 8 December 1644 | Imaculada Conceição |
| 13 | Sunday, 25 December 1644 | Natal |