diff --git a/controllers/index.go b/controllers/index.go
index 02e50de..3c04893 100644
--- a/controllers/index.go
+++ b/controllers/index.go
@@ -8,6 +8,9 @@ import (
 const DEFAULT_YEAR = 1765
 
 func GetIndex(fiber *fiber.Ctx) error {
-	_ = xmlmodels.Get()
-	return fiber.Render("/", nil)
+	lib := xmlmodels.Get()
+	// Years
+	years, yearmap := lib.Years()
+
+	return fiber.Render("/", map[string]any{"years": years, "yearmap": yearmap})
 }
diff --git a/lenz.go b/lenz.go
index 0b26ba0..ef2a694 100644
--- a/lenz.go
+++ b/lenz.go
@@ -43,12 +43,14 @@ func main() {
 	}
 
 	// INFO: the lib, engine and storage objects passed to the server should never be recreated.
-	err = xmlmodels.New(dir, commit.Hash)
+	lib, err := xmlmodels.Parse(dir, commit.Hash)
 	if err != nil {
 		panic(err)
 	}
 
 	engine := templating.New(&views.LayoutFS, &views.RoutesFS)
+	engine.AddFuncs(lib.FuncMap())
+
 	storage := memory.New(memory.Config{
 		GCInterval: 24 * time.Hour,
 	})
diff --git a/templating/engine.go b/templating/engine.go
index bb99d0a..599b88f 100644
--- a/templating/engine.go
+++ b/templating/engine.go
@@ -11,7 +11,6 @@ import (
 	"sync"
 
 	"github.com/Theodor-Springmann-Stiftung/lenz-web/helpers/functions"
-	"github.com/gofiber/fiber/v2"
 	"golang.org/x/net/websocket"
 )
 
@@ -180,9 +179,17 @@ func (e *Engine) AddFunc(name string, fn any) {
 	e.FuncMap[name] = fn
 }
 
+func (e *Engine) AddFuncs(funcs template.FuncMap) {
+	e.mu.Lock()
+	defer e.mu.Unlock()
+	for k, v := range funcs {
+		e.FuncMap[k] = v
+	}
+}
+
 func (e *Engine) Render(out io.Writer, path string, data any, layout ...string) error {
 	e.mu.RLock()
-	ld := data.(fiber.Map)
+	ld := data.(map[string]any)
 	if e.GlobalData != nil {
 		maps.Copy(ld, e.GlobalData)
 	}
diff --git a/views/routes/body.gohtml b/views/routes/body.gohtml
index 9b12097..9f110b2 100644
--- a/views/routes/body.gohtml
+++ b/views/routes/body.gohtml
@@ -1 +1,15 @@
-Hello from body! What!
+{{ $model := . }}
+
+{{- if .years -}}
+	{{- range $y := .years -}}
+		<div>
+			{{- printf "%d " $y -}}
+			{{- $letters := index $model.yearmap $y -}}
+			{{- len $letters }}
+			{{ range $l := $letters -}}
+				<div>{{ $l.Letter }}</div>
+				<div>{{ $l.Earliest.Text -}}</div>
+			{{- end -}}
+		</div>
+	{{- end -}}
+{{- end -}}
diff --git a/xml/xmlprovider.go b/xml/xmlprovider.go
index b968597..d6ad97b 100644
--- a/xml/xmlprovider.go
+++ b/xml/xmlprovider.go
@@ -89,13 +89,13 @@ func (p *XMLParser[T]) Serialize(dataholder XMLRootElement[T], path string, late
 // It deletes all items that have not been parsed in the last commit,
 // and whose filepath has not been marked as failed.
 func (p *XMLParser[T]) Cleanup(latest ParseMeta) {
-	todelete := make([]string, 0)
+	todelete := make([]any, 0)
 	toappend := make([]*T, 0)
 	p.Infos.Range(func(key, value interface{}) bool {
 		info := value.(ItemInfo)
 		if !info.Parse.Equals(latest) {
 			if !latest.Failed(info.Source) {
-				todelete = append(todelete, key.(string))
+				todelete = append(todelete, key)
 			} else {
 				item, ok := p.Items.Load(key)
 				if ok {
@@ -165,7 +165,7 @@ func (p *XMLParser[T]) Info(id string) ItemInfo {
 	return info.(ItemInfo)
 }
 
-func (p *XMLParser[T]) Item(id string) *T {
+func (p *XMLParser[T]) Item(id any) *T {
 	item, ok := p.Items.Load(id)
 	if !ok {
 		return nil
diff --git a/xml/xsdtime.go b/xml/xsdtime.go
index 6d498f2..bd4e4e2 100644
--- a/xml/xsdtime.go
+++ b/xml/xsdtime.go
@@ -231,17 +231,17 @@ func (xsdd XSDDate) Type() XSDDatetype {
 }
 
 func (xsdd *XSDDate) Validate() bool {
-	if xsdd.error {
+	if xsdd.error || len(xsdd.base) == 0 {
 		xsdd.state = Invalid
 		return false
 	}
 
 	xsdd.state = xsdd.inferState()
-	if xsdd.state != Invalid {
-		return true
+	if xsdd.state == Invalid {
+		return false
 	}
 
-	return false
+	return true
 }
 
 func (xsdd *XSDDate) parseError(s string) error {
@@ -309,6 +309,56 @@ func (xsdd XSDDate) inferState() XSDDatetype {
 	return Invalid
 }
 
+func (xsdd XSDDate) Before(other XSDDate) bool {
+	if xsdd.Year < other.Year {
+		return true
+	} else if xsdd.Year > other.Year {
+		return false
+	}
+
+	if xsdd.Month < other.Month {
+		return true
+	} else if xsdd.Month > other.Month {
+		return false
+	}
+
+	if xsdd.Day < other.Day {
+		return true
+	}
+
+	return false
+}
+
+func (xsddate *XSDDate) Compare(other *XSDDate) int {
+	if !xsddate.Validate() {
+		return -1
+	}
+
+	if !other.Validate() {
+		return 1
+	}
+
+	if xsddate.Year < other.Year {
+		return -1
+	} else if xsddate.Year > other.Year {
+		return 1
+	}
+
+	if xsddate.Month < other.Month {
+		return -1
+	} else if xsddate.Month > other.Month {
+		return 1
+	}
+
+	if xsddate.Day < other.Day {
+		return -1
+	} else if xsddate.Day > other.Day {
+		return 1
+	}
+
+	return 0
+}
+
 func validDay(i int) bool {
 	if i < 1 || i > 31 {
 		return false
diff --git a/xmlmodels/common.go b/xmlmodels/common.go
index 2a47b3d..bfb2832 100644
--- a/xmlmodels/common.go
+++ b/xmlmodels/common.go
@@ -17,3 +17,23 @@ type Date struct {
 	Cert      string             `xml:"cert,attr"`
 	Text      string             `xml:",chardata"`
 }
+
+func (d *Date) Sort() *xmlparsing.XSDDate {
+	if d.NotBefore.Validate() {
+		return &d.NotBefore
+	}
+	if d.From.Validate() {
+		return &d.From
+	}
+	if d.When.Validate() {
+		return &d.When
+	}
+	if d.To.Validate() {
+		return &d.To
+	}
+	if d.NotAfter.Validate() {
+		return &d.NotAfter
+	}
+
+	return nil
+}
diff --git a/xmlmodels/library.go b/xmlmodels/library.go
index 8269a85..93bc1a4 100644
--- a/xmlmodels/library.go
+++ b/xmlmodels/library.go
@@ -2,8 +2,11 @@ package xmlmodels
 
 import (
 	"fmt"
+	"html/template"
 	"log/slog"
+	"maps"
 	"path/filepath"
+	"slices"
 	"strconv"
 	"strings"
 	"sync"
@@ -30,6 +33,8 @@ type Library struct {
 	Letters    *xmlparsing.XMLParser[Letter]
 	Traditions *xmlparsing.XMLParser[Tradition]
 	Metas      *xmlparsing.XMLParser[Meta]
+
+	cache sync.Map
 }
 
 func (l *Library) String() string {
@@ -89,6 +94,7 @@ func (l *Library) Parse(source xmlparsing.ParseSource, baseDir, commit string) e
 	// INFO: this lock prevents multiple parses from happening at the same time.
 	l.mu.Lock()
 	defer l.mu.Unlock()
+	l.cache.Clear()
 
 	wg := sync.WaitGroup{}
 	meta := xmlparsing.ParseMeta{
@@ -233,3 +239,73 @@ func (l *Library) cleanup(meta xmlparsing.ParseMeta) {
 
 	wg.Wait()
 }
+
+func (l *Library) Years() ([]int, map[int][]Meta) {
+	if years, ok := l.cache.Load("years"); ok {
+		if yearmap, ok := l.cache.Load("yearmap"); ok {
+			return years.([]int), yearmap.(map[int][]Meta)
+		}
+	}
+
+	mapYears := make(map[int][]Meta)
+	for item := range l.Metas.Iterate() {
+		earliest := item.Earliest()
+		if earliest != nil {
+			mapYears[earliest.Sort().Year] = append(mapYears[earliest.Sort().Year], item)
+		}
+	}
+
+	ret := slices.Collect(maps.Keys(mapYears))
+	slices.Sort(ret)
+
+	for _, items := range mapYears {
+		slices.SortFunc(items, func(a, b Meta) int {
+			return a.Earliest().Sort().Compare(b.Earliest().Sort())
+		})
+	}
+	l.cache.Store("years", ret)
+	l.cache.Store("yearmap", mapYears)
+	return ret, mapYears
+}
+
+func (l *Library) LettersForYear(year int) (ret []Meta) {
+	for l := range l.Metas.Filter(func(item Meta) bool {
+		return item.Earliest().Sort().Year == year
+	}) {
+		ret = append(ret, l)
+	}
+	return
+}
+
+func (l *Library) Person(id int) (ret *PersonDef) {
+	ret = l.Persons.Item(id)
+	return
+}
+
+func (l *Library) Place(id int) (ret *LocationDef) {
+	ret = l.Places.Item(id)
+	return
+}
+
+func (l *Library) GetPersons(id []int) (ret []*PersonDef) {
+	for _, i := range id {
+		ret = append(ret, l.Person(i))
+	}
+	return
+}
+
+func (l *Library) GetPlaces(id []int) (ret []*LocationDef) {
+	for _, i := range id {
+		ret = append(ret, l.Place(i))
+	}
+	return
+}
+
+func (l *Library) FuncMap() template.FuncMap {
+	return template.FuncMap{
+		"Person":  l.Person,
+		"Place":   l.Place,
+		"Persons": l.GetPersons,
+		"Places":  l.GetPlaces,
+	}
+}
diff --git a/xmlmodels/meta.go b/xmlmodels/meta.go
index c13f66c..b658fa8 100644
--- a/xmlmodels/meta.go
+++ b/xmlmodels/meta.go
@@ -3,6 +3,7 @@ package xmlmodels
 import (
 	"encoding/json"
 	"encoding/xml"
+	"iter"
 
 	xmlparsing "github.com/Theodor-Springmann-Stiftung/lenz-web/xml"
 )
@@ -17,6 +18,28 @@ type Meta struct {
 	Recieved    []Action                `xml:"recieved"`
 }
 
+func (m *Meta) Earliest() *Date {
+	var earliest *Date
+
+	for _, action := range m.Sent {
+		if earliest == nil || action.Earliest().Sort().Before(*earliest.Sort()) {
+			earliest = action.Earliest()
+		}
+	}
+
+	if earliest != nil {
+		return earliest
+	}
+
+	for _, action := range m.Recieved {
+		if earliest == nil || action.Earliest().Sort().Before(*earliest.Sort()) {
+			earliest = action.Earliest()
+		}
+	}
+
+	return earliest
+}
+
 func (m Meta) Keys() []any {
 	return []any{m.Letter}
 }
@@ -33,8 +56,30 @@ func (m Meta) String() string {
 	return string(json)
 }
 
+func (m Meta) SendRecieved() iter.Seq2[*Action, *Action] {
+	return func(yield func(*Action, *Action) bool) {
+		for i, sent := range m.Sent {
+			var rec *Action
+			if i < len(m.Recieved) {
+				rec = &m.Recieved[i]
+			}
+			if !yield(&sent, rec) {
+				return
+			}
+		}
+	}
+}
+
 type Action struct {
-	Dates   []Date       `xml:"date,attr"`
+	Dates   []Date       `xml:"date"`
 	Places  []RefElement `xml:"place"`
 	Persons []RefElement `xml:"person"`
 }
+
+func (a *Action) Earliest() *Date {
+	if len(a.Dates) == 0 {
+		return nil
+	}
+
+	return &a.Dates[0]
+}
diff --git a/xmlmodels/public.go b/xmlmodels/public.go
index f6189b3..a280663 100644
--- a/xmlmodels/public.go
+++ b/xmlmodels/public.go
@@ -27,14 +27,14 @@ func Get() *Library {
 	return lib
 }
 
-func New(dir, hash string) error {
-	Set(NewLibrary())
-	return Parse(dir, hash)
-}
-
-func Parse(dir, hash string) error {
-	if hash == "" {
-		return lib.Parse(xmlparsing.Path, dir, hash)
+func Parse(dir, hash string) (*Library, error) {
+	if lib == nil {
+		Set(NewLibrary())
 	}
-	return lib.Parse(xmlparsing.Commit, dir, hash)
+
+	if hash == "" {
+		return Get(), lib.Parse(xmlparsing.Path, dir, hash)
+	}
+
+	return Get(), lib.Parse(xmlparsing.Commit, dir, hash)
 }