Exact location: https://plus.codes/8CCGPRPW+WF

In the grassy hill over the the lake, close to "Cafetaria do Museu Gulbenkian".

Look for a woman with a wide-brimmed hat.

Cross-posted to LW: https://www.lesswrong.com/events/N6jmniPrPpfXcoLAn/acx-ea-lisbon-june-2022-meetup