diff --git a/internal/calendar/option.go b/internal/calendar/option.go
new file mode 100644
index 0000000..5ac7438
--- /dev/null
+++ b/internal/calendar/option.go
@@ -0,0 +1,18 @@
+package calendar
+
+import (
+	"fmt"
+)
+
+type Option func(*Service) error
+
+func WithCalendar(key string, calendarId string) Option {
+	return func(s *Service) error {
+		_, err := s.CalendarList.Get(calendarId).Do()
+		if err != nil {
+			return fmt.Errorf("cannot find calendar entry with id %q: %w", calendarId, err)
+		}
+		s.calIds[key] = calendarId
+		return nil
+	}
+}
diff --git a/internal/calendar/service.go b/internal/calendar/service.go
index 130a02c..3acb3eb 100644
--- a/internal/calendar/service.go
+++ b/internal/calendar/service.go
@@ -3,7 +3,6 @@ package calendar
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
 	"log"
 	"net/http"
@@ -19,10 +18,11 @@ import (
 const tokFile = "token.json"
 
 type Service struct {
+	calIds map[string]string
 	*calendar.Service
 }
 
-func NewService(ctx context.Context, credJson string) *Service {
+func NewService(ctx context.Context, credJson string, opts ...Option) (*Service, error) {
 	b := []byte(credJson)
 
 	config, err := google.ConfigFromJSON(b, calendar.CalendarReadonlyScope)
@@ -36,27 +36,35 @@ func NewService(ctx context.Context, credJson string) *Service {
 		log.Fatalf("Unable to retrieve Calendar client: %v", err)
 	}
 
-	return &Service{srv}
+	s := &Service{
+		Service: srv,
+		calIds:  make(map[string]string),
+	}
+
+	for _, opt := range opts {
+		err := opt(s)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return &Service{Service: srv}, nil
 }
 
 // TODO: implement create event, list events in a period, delete event
-
-// TODO: Delete this. It is just for Proof of Concept
-func (s Service) ListNextEvents() (*calendar.Events, error) {
-	t := time.Now().Format(time.RFC3339)
-	events, err := s.Events.List("primary").ShowDeleted(false).
-		SingleEvents(true).TimeMin(t).MaxResults(10).OrderBy("startTime").Do()
-	if err != nil {
-		return nil, fmt.Errorf("unable to retrieve next ten of the user's events: %w", err)
-	}
-	if len(events.Items) == 0 {
-		return nil, errors.New("no upcoming events found")
-	} else {
-		// TODO: return a custom type
-		return events, nil
+func (s *Service) Create(from, to time.Time) (*calendar.Event, error) {
+	l := s.CalendarList.List()
+	r, e := l.Do()
+	log.Println(e)
+	for _, c := range r.Items {
+		log.Printf("%+v: %s", c.Summary, c.Id)
 	}
+	return nil, nil
 }
 
+func (s *Service) List(from, to time.Time) (*calendar.Events, error) { return nil, nil }
+func (s *Service) Delete(id int) error                               { return nil }
+
 // Retrieve a token, saves the token, then returns the generated client.
 func getClient(ctx context.Context, config *oauth2.Config) *http.Client {
 	// The file token.json stores the user's access and refresh tokens, and is
diff --git a/internal/server/server.go b/internal/server/server.go
index 37df58e..a883933 100644
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -20,6 +20,7 @@ import (
 	"github.com/rjNemo/rentease/config"
 	"github.com/rjNemo/rentease/internal/auth"
 	"github.com/rjNemo/rentease/internal/booking"
+	"github.com/rjNemo/rentease/internal/calendar"
 	"github.com/rjNemo/rentease/internal/pdf"
 )
 
@@ -28,6 +29,7 @@ type Server struct {
 	bs        *booking.Service
 	as        *auth.Service
 	ps        *pdf.PdfService
+	cs        *calendar.Service
 	hc        *config.Host
 	addr      string
 	secretKey string
@@ -90,7 +92,7 @@ func WithApiKey(apiKey string) Option {
 	}
 }
 
-func New(bs *booking.Service, as *auth.Service, ps *pdf.PdfService, hc *config.Host, opts ...Option) (*Server, error) {
+func New(bs *booking.Service, as *auth.Service, ps *pdf.PdfService, cs *calendar.Service, hc *config.Host, opts ...Option) (*Server, error) {
 	option := new(options)
 	for _, opt := range opts {
 		err := opt(option)
@@ -104,6 +106,7 @@ func New(bs *booking.Service, as *auth.Service, ps *pdf.PdfService, hc *config.H
 		bs:        bs,
 		as:        as,
 		ps:        ps,
+		cs:        cs,
 		hc:        hc,
 		addr:      fmt.Sprintf("0.0.0.0:%d", *option.port),
 		secretKey: *option.secretKey,
diff --git a/main.go b/main.go
index 3f21675..3204cf6 100644
--- a/main.go
+++ b/main.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"embed"
 	"fmt"
+	"log"
 	"os"
 	"os/signal"
 	"strconv"
@@ -17,6 +18,7 @@ import (
 	"github.com/rjNemo/rentease/config"
 	"github.com/rjNemo/rentease/internal/auth"
 	"github.com/rjNemo/rentease/internal/booking"
+	"github.com/rjNemo/rentease/internal/calendar"
 	"github.com/rjNemo/rentease/internal/pdf"
 	"github.com/rjNemo/rentease/internal/server"
 )
@@ -72,6 +74,18 @@ func run(c context.Context, getEnv func(string) string) error {
 		return fmt.Errorf("error starting auth service %s", err)
 	}
 
+	creds := os.Getenv("CALENDAR_CREDENTIALS")
+	t2Id := os.Getenv("CALENDAR_ID_T2")
+	t3Id := os.Getenv("CALENDAR_ID_T3")
+
+	cs, err := calendar.NewService(ctx, creds,
+		calendar.WithCalendar("T2", t2Id),
+		calendar.WithCalendar("T3", t3Id),
+	)
+	if err != nil {
+		log.Fatalf("cannot build calendar service: %s", err)
+	}
+
 	p := getEnv("PORT")
 	port, err := strconv.Atoi(p)
 	if err != nil {
@@ -85,6 +99,7 @@ func run(c context.Context, getEnv func(string) string) error {
 		booking.NewService(db),
 		as,
 		ps,
+		cs,
 		config.NewHost(),
 		server.WithPort(port),
 		server.WithFileSystem(static),